The Spanish invasion of Portugal between 5 May and 24 November 1762 was a main military episode of the wider Seven Years' War, where Spain and France were heavily defeated by the Anglo-Portuguese Alliance (including broad popular resistance). It initially involved the forces of Spain and Portugal, before the French and British intervened in the conflict on the side of their respective allies. The war was also strongly marked by a national guerrilla warfare in the mountainous country, cutting off supplies from Spain, and a hostile peasantry that enforced a scorched earth policy as the invading armies approached, leaving the invaders starving and short of military supplies.
During the first invasion, 22,000 Spaniards commanded by Nicolás de Carvajal, Marquis of Sarria, entered the Province of Alto Trás-os-Montes (northeast of Portugal) having Oporto as their ultimate goal. After occupying some fortresses they were confronted with a national uprising. Taking advantage of the mountainous terrain, the guerrilla bands inflicted heavy losses on the invaders and practically cut off their communication lines with Spain, causing a shortage of essential supplies. Near starvation, the Spaniards tried to conquer Oporto quickly, but were defeated in the battle of Douro (1762) and in the battle of Montalegre before retreating to Spain. After this failure, the Spanish commander was replaced by Pedro Pablo Abarca de Bolea, Count of Aranda.
During the second invasion of Portugal (Province of Beira), 42,000 Franco-Spaniards under Aranda took Almeida and several other strongholds, while the Anglo-Portuguese army stopped another Spanish invasion of Portugal by the province of Alentejo, attacking at Valencia de Alcántara ( Spanish Extremadura), where a third Spanish corps was assembling for invasion.
The allies managed to stop the invading army in the mountains east of Abrantes, where the slope of the heights facing the Franco-Spanish army was abrupt but very soft on the side of the allies, which facilitated the supply and movements of the allies but acted as a barrier for the Franco-Spaniards. The Anglo-Portuguese also prevented the invaders from crossing the river Tagus and defeated them at Vila Velha.
The Franco-Spanish army (which had their supply lines from Spain cut off by the guerrillas) was virtually destroyed by a deadly scorched earth strategy: peasants abandoned all the villages around, taking with them or destroying the crops, food and all that could be used by the invaders, including the roads and houses. The Portuguese government also encouraged desertion among the invaders offering large sums to all deserters and defectors. The invaders had to choose between stay and starve or withdraw. The final outcome was the disintegration of the Franco-Spanish army, which was compelled to retreat to Castelo Branco (closer to the frontier) when a Portuguese force under Townshend made an encircling movement towards its rearguard. According to a British observer, the invaders suffered 30,000 losses (almost three-quarters of the original army), mainly caused by starvation, desertion and capture during the chase of the Franco-Spanish remnants by the Anglo-Portuguese army and peasantry.
Finally the allied army took the Spanish headquarters, Castelo Branco, capturing a large number of Spaniards, wounded and sick – who Aranda had abandoned when he fled to Spain, after a second allied encircling movement.
During the third invasion of Portugal, the Spaniards attacked Marvão and Ouguela but were defeated with casualties. The allied army left their winter quarters and chased the retreating Spaniards, taking some prisoners; and a Portuguese corps entered Spain taking more prisoners at Codicera.
On 24 November, Aranda asked for a truce which was accepted and signed by Lippe on 1 December 1762.
- 1 The Triple invasion of Portugal in a few words
- 2 Portuguese and Spanish neutrality in the Seven Years' War
- 3 The Franco-Spanish Ultimatum
- 4 The first invasion of Portugal (Trás-os-Montes)
- 5 The "tyrants of the sea" reorganize the Portuguese army
- 6 An aborted Spanish invasion (Alentejo)
- 7 The second invasion of Portugal (Beira)
- 8 La Lippe is rewarded
- 9 The third invasion of Portugal (Alentejo)
- 10 The reasons of a victory
- 11 The Spanish prestige according to the contemporaneous
- 12 A trial, two measures
- 13 The invasion in literature
- 14 Stalemate in South America
- 15 Notes
- 16 References
- 17 External links
"The first object of the allied governments of Spain and France was to invade Portugal, the ancient ally of Great Britain, which was supposed to be wholly incapable of defending itself against so formidable a confederacy…that feeble and defenceless kingdom was invaded shortly afterwards at three distinct points by three Spanish armies, such was the spirit of patriotism awaked among the peasantry by a few British officers, that the invaders were repulsed, and ultimately driven back in disgrace." — Studies in history
During the Seven Years' War, a British fleet under Admiral Boscawen attacked a French fleet in Portuguese waters in front of Lagos, Algarve, in 1759. Three French ships were captured and two burned. Portugal, though an old ally of Britain, had stated her neutrality in this war and accordingly, the Portuguese prime minister Pombal demanded satisfaction from Great Britain. The British government apologized to the Portuguese king, José I, by sending a special delegation to Lisbon,  yet the captured vessels were not returned, as demanded by France (Pombal had previously informed Pitt that he did not expect it).  The Portuguese government materially assisted the French garrisons that had taken refuge in Lagos after the battle. The French king, Louis XV, thanked José I for all the assistance given to the French sailors, although claiming for the navies. The case seemed settled, but Spain and France would use it as a pretext to invade Portugal four years later.
Portugal was having increasing difficulties in maintaining its neutrality in the Seven Years' War because of minor incidents between British residents and the French: on one occasion, the British consul in Faro secretly warned British frigates to enter the city's harbor and prevent the unloading of a French ship; and in Viana do Minho, British businessmen armed a boat and retook a captured English ship from a French corsair. However, the king and government of Portugal were strongly committed to keep the country out of the war.
On their part, the French were increasingly pressing a reluctant Spain to enter the war on their side (while beginning secret negotiations with Great Britain to end it).  Both countries eventually signed the famous III Compact Family (15 August 1761), a "continental system" mainly designed to isolate Britain in Europe.  However, British ships intercepted official correspondence from Spain to France and learned that there was a secret clause providing that Spain should declare war on Britain on 1 May 1762.   The British anticipated Spain, declaring war first on 2 January 1762.
Both Bourbon powers decided to force Portugal to join their Family Compact (the Portuguese king was married to a Bourbon, the Spanish king's sister). Spain and France sent an ultimatum to Lisbon (1 April 1762) stating that Portugal had to: 
- Terminate the Anglo-Portuguese Alliance replacing it with a new alliance with France and Spain.
- Close her ports to English ships and to interrupt all commerce with Great Britain both in Europe and within the Portuguese empire.
- Declare war on Great Britain
- Accept the occupation of Portuguese ports (including Lisbon and Oporto) by a Spanish army. Thus Portugal would be both "protected" and "liberated" from its British "oppressors".
Portugal was given four days to answer, after which the country would face an invasion by the forces of France and Spain. Both Bourbon powers hoped to benefit by diverting British troops from Germany to Portugal, while Spain hoped to seize Portugal and its empire. 
The Portuguese situation was desperate. The great Lisbon earthquake, tsunami and fire of 1755 had completely destroyed the Portuguese capital, killing tens of thousands and damaging most of the Portuguese fortresses. Rebuilding a new Lisbon left no money to sustain an army or navy; and even the military cadres who had died in the earthquake were not replaced by 1762. From 1750 onward the Brazilian gold supply (which made Portugal by far the largest gold owner on earth during the 18th century) started its irreversible decline, and the price of Brazilian sugar also fell as British and Dutch demand reduced. 
The Portuguese navy – which had been powerful during the 15th century, was reduced to only three ships of the line and some frigates. The general picture of the Portuguese "army" was calamitous: The regiments were incomplete, the military warehouses were empty, and there were no military hospitals. By November 1761, the troops had not been paid for a year and a half (they received 6 months payment on the eve of war), and many soldiers lived from robbery, or "assassinating for a livelihood".  Military discipline was a distant memory and the greater part of the troops was "without uniforms and without arms".  When French Ambassador O’Dunne delivered the ultimatum (1 April 1762), a party of sergeants with a captain knocked on his door, begging for alms.  Recruitment often included trapping vagrants and transients during popular gatherings. The Count of Saint-Priest, French ambassador in Portugal, reported: "It was impossible to find an army in greater disorder than in Portugal. When the Count of Lippe [the supreme allied commander, sent by England] arrived, the army had as Field Marshal the Marquis de Alvito, who had never learned to shoot a rifle or command a regiment, even in peacetime. The colonels, mostly great Lords, placed as officers in their regiments their valets. It was very common to see soldiers, mostly ragged, begging for alms [even the sentinels of the royal palace]. This state of disorder had just finished shortly before I arrived. We need to be fair. The Count of Lippe established discipline, forced officials to choose between the position in the regiment or his previous condition as valets. (…).With the aid of some foreign officials, military bodies were disciplined and when I arrived, were already trained." 
To reinforce their ultimatum and press the Portuguese government, Spanish and French troops started gathering on the Portuguese northern frontiers since 16 March 1762, alleging it was merely a "preventive army". The Portuguese government declared its intention of defending to the last. As soon as news of the entry of Spanish troops into the North of the kingdom reached the Court, Portugal declared war both on Spain and France (18 May 1762), asking for British financial and military assistance. Spain and France declared war on 15 and 20 June, respectively.
"The campaign had been commenced by the Spaniards on the side of Tras os Montes, in which province Miranda, Braganza, and some other towns, had fallen into their hands. They next resolved to proceed against Oporto, but this design was frustrated by the bravery of the peasants, who took possession of the defiles, and compelled the Spanish army to a disorderly retreat. Disappointed in this quarter the enemy turned their steps towards the province of Beira [abandoning Trás-os-Montes] ..." — Orderly book of Lieut. Gen John Burgoyne
On 30 April 1762 a Spanish force penetrated into Portugal through the province of Trás-os-Montes and posted a proclamation entitled "reasons for entering Portugal", in which the Spaniards declared that they were coming not as enemies, but as friends and liberators who came to free the Portuguese people from the "heavy shackles of England",  the "tyrant of the seas". On May 5, the Marquis of Sarria, leading an army of 22,000 men started the real invasion.  Portugal declared war on both Spain and France (18 May 1762).
Miranda, the only fortified and provisioned fortress of the province, was besieged on 6 May 1762, but an accidental and huge powder explosion (20 tons) killed four hundred and opened two breaches in the ramparts, forcing the surrender on 9 May 1762. Bragança (12 May), Chaves (21 May), and Torre de Moncorvo (23 May) were open cities without soldiers, and were occupied without firing a gun. There were neither fortresses with intact walls nor regular troops inside the entire province of Trás-os-Montes (neither powder nor provisions).  The Spanish general joked about the complete absence of Portuguese soldiers across the province: "I can not discover where these insects are."  At first, the relationship of the invaders with the civil population was apparently excellent. The Spaniards paid double for the provisions they acquired, and there wasn't a single shotgun.  But Madrid had committed a double error: since the Spaniards believed that the simple show of power would be enough to induce Portugal to submission, they entered the country almost without provisions, which would undermine the entire campaign.  They also assumed that the country could provide them all the necessary food. When this proved an illusion, the Spanish army imposed forced requisitions of provisions to the populations. These were the trigger for a popular revolt, with war for food feeding war. 
Victory seemed a matter of time, and in Madrid, it was confidently expected that the fall of Oporto was imminent, but suddenly the invaders were confronted with a national rebellion, which spread around the Provinces of Trás-os-Montes and Minho. Francisco Sarmento, the governor of Trás-os-Montes, posted a declaration ordering the people to resist the Spaniards or be branded rebels. The Spaniards were confronted by deserted villages with neither food nor peasants to build roads for the army. Together with some militias and ordenances (respectively a kind of Portuguese military institution of 2nd and 3rd line), gangs of civilians armed with sickles and guns attacked the Spanish troops, taking advantage of the mountainous terrain.  The Spaniards suffered heavy losses and high rates of disease. Several reports on the ground (published in the British press in 1762) confirm this: "[Province of] Beira. Almeida, June 12, (...) the Enemy [Spaniards], to the number of eight thousand has entered the frontier… several parties have rallied forth from the camp, and had pillaged the villages upon that frontier, and had not even spared the churches; but that these parties had been driven back by the Portuguese militia, who had killed and taken prisoners upwards of two hundred Spaniards (...). [Province of] Minho…June 20…those [Spaniards] who retired from Villa Real and Mirandela towards Miranda, were attacked upon their march by the militia… who killed some of the Spaniards, and took twenty odd prisoners…we have advice of the 22d [June], that a convoy of sixty mules, laden with provisions, had been taken from the enemy about two leagues from Chaves." 
According to a French contemporary source, more than 4,000 Spaniards died in the hospital of Braganza,  both from wounds and disease. Many others were killed by the guerrillas, taken prisoners, or died from starvation – which was becoming a growing problem. The Portuguese nationalism and the atrocities committed by the Spanish army against peasant villages – mainly during food expeditions – were the fuel for the revolt. Even the King of Spain Charles III, in his declaration of war to Portugal (15 June 1762) – one month and a half after the start of the invasion and almost one month after the Portuguese declaration of war on Spain – complained that many Portuguese populations, conducted by undercover officers, had treacherously killed several Spanish detachments.  In another example, the Portuguese Corregidor of Miranda reported in August 1762 that the invading forces in the north had
"experienced a mortal hatred from the countrymen, who have made them war, and do not spare neither soldiers nor sutlers…and initially even killed defectors, accusing them of being spies. No countrymen take groceries to the stronghold… and sutlers don’t dare seeking them out without an escort of more than 30 men, because of fewer, none of them comes back to the fortress." 
The invaders were forced to split their forces in order to protect conquered strongholds, find food, and escorting convoys with supplies. The food for the army had to come from Spain itself, which made it vulnerable to attacks. Unless the Spanish army could quickly take Oporto, starvation would make their situation untenable.
A Spanish force of 3,000 to 6,000 men led by O'Reilly left Chaves, and advanced towards Oporto. This caused great alarm among the British in the city, where their community had many stores with provisions and 30,000 pipes of wine waiting shipment. Measures for evacuating them were initiated by the British Admiralty, while the Portuguese governor of Oporto was ordered to leave the city (which he didn’t).  But when the Spaniards tried to cross the River Douro between Torre de Moncorvo and Vila Nova de Foz Côa, they met O’Hara and his Portuguese force of hundreds of peasants with guns and some Ordenances, helped by women and children in the hills of the southern margin (May 25). In the battle that followed, the Spanish assaults were completely beaten off with losses.   Panic took possession of the invaders, who made a hasty retreat and were chased by the peasants until Chaves (the expedition's starting point). In the words of the contemporaneous French general Dumouriez, who went to Portugal in 1766 to study the campaign of 1762 in loco,  writing a famous report sent to the King of Spain and to the French foreign minister Choiseul:
" O'Reilly... turned back and made a very disorderly retreat; at Villa Pouca, and as far as Chaves, the peasants harassed him exceedingly, and had the glory of driving him back with loss and disgrace, though their number did not exceed 600, nor had they a single military man with them. This feat was highly celebrated in Portugal, and the particulars of it repeated with great pride. The failure in this operation occasioned the retreat of the Spanish army [from Portugal] to Zamora [Spain] (pp. 18-19).  (...). He owed this defeat to the appearance of fair (p.249) ..." — In An Account of Portugal, as it Appeared in 1766 to Dumouriez.
On May 26, another part of the Spanish army that had marched from Chaves towards the province of Minho (Oporto being the final goal), engaged in battle with the Portuguese ordenances at the mountains of Montalegre and the outcome was similar: the Spaniards had to retreat with losses.
"... After having become masters of Miranda, Bragança and Chaves, places with no garrisons or walls, the Spanish detached 12 thousand men, part on Montalegre, part on Vila Real. The division which went on Montalegre was strong of 4,000 combatants; however burghers, most of whom had neither rifles nor swords, with some companies of the King's troops, routed this body and caused it to lose many people. — Contemporary account of the Battle of Montalegre in the jornal Le Nouvelliste Suisse , July 1762.
An army of 8,000 Spaniards sent towards Almeida (in the province of Beira) also suffered defeat: the invaders were driven back after suffering 200 casualties inflicted by the militias,  and 600 dead in a failed assault to the fortress of Almeida (according to contemporary British sources) 
Finally, reinforcements were sent to Oporto and the province of Trás-os-Montes, who occupied the passes and defiles, endangering the Spanish withdrawal, and at the same time, making it inevitable.  Letters published in the British press few days later added: "This is all the information we have had to this day, May 29 . The officers cannot find terms to express the courage of the militia and the zeal and eagerness which the people show to be engaged with the enemy." 
The outcome of the battle of Douro proved crucial for the failure of the Spanish invasion,  because as Dumouriez explained: "Portugal was at that time without troops and planet-struck; had the [Spanish] army advanced rapidly upon Oporto it must have taken it without firing a gun. Great resources would have been found there, both in money, stores and provisions, and an excellent climate; the Spanish troops would not have perished as they did, with hunger and want of accommodations; the face of affairs would have been totally changed." 
In addition to these setbacks, and similarly to the Napoleonic soldiers a few decades later, the Spaniards were experiencing carnage. A contemporary document notes that it was impossible to walk in the mountains of the province of Trás-os-Montes because of the nauseating odour of countless Spanish corpses, which the peasants refused – motivated by pure hate – to bury.  Even inside the occupied cities the invaders were not safe: of about half a thousand miqueletes who entered Chaves (21 May 1762), only eighteen were still alive by the end of June.  According to the Spanish military historian José Luis Terrón Ponce, the total Spanish casualties during the first invasion of Portugal (caused by the guerrillas, diseases and desertion) was over 8,000 men.  (In 1766, Dumouriez had evaluated this number at 10,000 losses, and he recommended the Spaniards to avoid this province of Trás-os Montes in a future invasion). 
Having failed the main military target of the campaign (Oporto, the second city of the kingdom), suffering terrible losses from famine and the guerrillas (who cut off their food supplies), and eventually threatened by the advancing Portuguese regular army at Lamego – which could split the two wings of the Spanish army (the force trying to reach the south bank of the Douro and the other aiming Oporto through the mountains)   the diminished and demoralized Spanish army was forced to withdraw towards Spain (end of June 1762), abandoning all their conquests with the only exception of the city of Chaves (in the frontier).    As a French military put it:
"The Spaniards have always been unhappy in their expeditions against the Province of Trás-os-Montes. During the war of 1762, they were repulsed by the peasants alone, after experiencing great losses." — Cited in Lettres Historiques et Politiques sur le Portugal
The first invasion had been defeated by the peasants alone, virtually without Portuguese regular troops or British troops,  and very soon the Marquis of Sarria, the Spanish commander, would be replaced by Count of Aranda.  In order to save his and Charles III's face, Sarria "asked" to be removed for "reasons of health" immediately after the conquest of Almeida and after receiving the Order of the Golden Fleece: "The old Marquis of Sarria was rewarded for his failure with the Order of the Golden Fleece, and his 'voluntary resignation' was accepted."  Spain had lost the opportunity of defeating Portugal before the arrival of British troops and their assembling with the Portuguese regular forces.
Many civilians were killed or transferred into Spain, together with the silver of the churches and the horses of the villages. A contemporary account published in British press during this invasion is quite revealing:
"The Spaniards, instead of advancing boldly to face their enemies, content themselves with dispatching flying parties from their camp, who commit unheard of barbarities among the small villages; robbing and murdering the inhabitants; setting fire to their crops, and not even sparing the sacred furniture belonging to their chapels. On their retreat from Braganza [at the end of the invasion], they plundered the college and church, as well as the houses of several of the principal people; whom, together with several priests, they carried with them into Spain. They also killed several peasants of that neighbourhood in cold blood." — The Gentleman's and London Magazine: Or Monthly Chronologer, 1741-1794
Meanwhile, a British expeditionary force landed: the 83rd, 91st regiments of infantry, together with the major portion of the 16th light dragoons (all led by Major General George Townshend) arrived at Lisbon in May; while the 3rd, 67th, 75th, and 85th regiments of foot along with two Royal Artillery companies (the main force) only landed from Belle-Isle, in July 1762. The total number of this force is known with exactitude (from official documents): 7,104 officers and men of all arms.  Great Britain also sent provisions, ammunitions and a loan of £200,000 to the Portuguese ally.
There was some friction between both allies, caused by problems of language, religion and envy; the Portuguese officers felt uncomfortable with being commanded by strangers, and especially with the salaries of their British peers, which was double theirs (so that British officers could keep the salary they had in the British army). In addition to the difficulty of feeding British troops in Portugal, Lippe successfully faced another huge problem: the recreation of the Portuguese army and its integration with the British one. La Lippe selected only 7,000 to 8,000 men out of the 40,000 Portuguese soldiers who were submitted to him, and dismissed all the others as useless or unfit for military service.  Thus, the complete allied army in campaign was about 15,000 regular soldiers (half Portuguese and half British). The militias and ordenances (respectively a kind of Portuguese military institution of 2nd and 3rd line, around 25,000 men in total) were only used to garrison the fortresses whilst some regular troops (1st line) remained in the north of Portugal to face the Spanish troops of Galicia. These 15,000 men had to face a combined army of 42,000 invaders (of whom were 30,000 Spaniards led by Count of Aranda, and 10,000 to 12,000 French commanded by Prince de Beauvau).
Lippe would eventually be successful both in the integration of the two armies as well as in the final action. As noted by historian Martin Philippson:  "The new leader was able, in a short time, to reorganize the Portuguese army, and with it, re-enforced by the English, he drove the Spaniards, in spite of their superiority in numbers, across the frontiers, (...)" 
The Franco-Spanish army had been divided into three divisions:  the Northeast Division, in Galicia, invaded the northeast Portuguese provinces of Trás-os-Montes and Minho with Oporto as its ultimate goal (first invasion of Portugal, May–June 1762); the central division (reinforced by French troops and the remnants of the northeast division) – which afterwards invaded the Portuguese province of Beira (centre of Portugal) towards Lisbon (second invasion of Portugal, July–November 1762); and finally a southern army's corps (near Valencia de Alcántara), designed to invade the province of Alentejo, in the south of Portugal.
The successes of the Franco-Spanish army in the beginning of the second invasion of Portugal (Beira) caused such alarm that D. José I pressured his commander, Count of Lippe, for an offensive campaign. Since the enemy was gathering troops and ammunitions in the region of Valencia de Alcántara, near Alentejo – preparing a third Spanish invasion – Lippe chose to take a preventive action by attacking the invader on his own ground, in Estremadura. The troops around Valencia de Alcántara were the advanced lines of the Spanish third corps (southern division), and this city was a main supply depôt, containing magazines and a park of artillery. The allies had the surprise factor on their side as the disparity of numbers and resources was so great that the Spaniards did not expect such a risky operation: they had neither barricades nor advanced piquets, or even guards, except in the City's great square.
On the morning of 27 August 1762, a force of 2,800 Anglo-Portuguese under Burgoyne attacked and took Valencia de Alcántara, defeated one of the best Spanish regiments (the Seville's regiment), killed all the soldiers that resisted, captured three flags and several troops and officers – including the Major-General Don Miguel de Irunibeni, responsible for the invasion of Alentejo, and who had come into the city the day before (along with two colonels, two captains and seventeen subaltern officers). Many arms and ammunition were captured or destroyed.
The Battle of Valencia de Alcántara not only galvanized the Portuguese army at a critical phase of the war (in beginning of the second invasion), but also prevented a third invasion of Portugal by the Alentejo,  a plain and open province, through which the powerful Spanish chivalry could march towards the vicinity of Lisbon without opposition.
Burgoyne was rewarded by the King of Portugal, D. José I, with a large diamond ring, together with the captured flags, while his international reputation skyrocketed.
"... the main central attack on Portugal [second invasion] failed utterly ... partly through the skilful measures of the prince of Lippe, who had been placed in charge of the Portuguese army, and strengthened by 7,000 British troops, partly through the bold partisan enterprises carried out against their line of communications by General Burgoyne [and the guerrillas] ... But mainly the invasion failed through the absolute lack of munitions and food; the Portuguese – as was their wont – had swept the country side clean [a deadly scorched earth strategy], (...). After starving for some weeks in a roadless wilderness, the Spanish army retired into Estremadura [Spain] in a sad state of dilapidation. Next spring Charles III sued for peace." — Journal of the Royal United Service Institution
After being defeated in the province of Trás-os-Montes,  Sarria's shattered army returned into Spain by Ciudad Rodrigo and gathered with the Centre's army. Here, the two Spanish corps were joined by a French army of 12,000 men, led by Prince de Beauvau, putting the total number of the Bourbon invaders at 42,000 men. Thus, the original plan to converge on Oporto through Trás-os Montes was abandoned and replaced by a new one:  this time Portugal would be invaded through the province of Beira, in the east centre of the country, and the target would be Lisbon. Sarria was replaced by the Count of Aranda, while the Spanish minister Esquilache went to Portugal to support and organize the logistic of the Spanish army so that it had food for 6 months.  Considering the complete unpreparedness of the Portuguese army, and the huge disparity of forces (30,000 Spaniards plus 12,000 French versus 7,000-8,000 Portuguese plus 7,104 British),    the Marquis of Pombal assembled 12 ships in the Tagus estuary prepared, if necessary, to transfer the Portuguese king and court into Brazil.
In the beginning of the second invasion, A British observer – after describing the Portuguese soldiers as the "wretched troops" he ever saw, who were "often five days together without bread, and the horses without forage" – wrote he was apprehensive that Lippe, overwhelmed by difficulties, ended up asking for resignation.  Indeed, at first the Franco-Spanish army occupied several fortresses with ruined walls and without regular troops:  Alfaiates, Castelo Rodrigo, Penamacor, Monsanto, Salvaterra do Extremo, Segura (17 September 1762), Castelo Branco (18 September), and Vila Velha (2 October) surrendered practically without firing a gun, as lamented by the allied commander, Lippe. After the war, several fortresses governors would be tried and convicted for treason and cowardice.
Almeida, the main fortress of the Province, was in such a state that O’Hara,  the British officer who led the guerrilleros and militias at the battle of Douro, advised the stronghold 's commander to take his garrison out of the fortress and put it in nearby country where defence could be much more easily sustained.  (The commander responded that he couldn’t do that without superior orders). Its garrison, consisting only in two regular regiments and three militia regiments (totalling 3,000 to 3, 500 men), experienced a drastic reduction in their numbers for desertion, during the enemy's approaching and siege.   Facing an overwhelming combination of 24,000 Spanish and 8,000 French,  and poorly commanded by an incompetent, the octogenarian Palhares (whose substitute sent by the government did not arrive on time), the remaining 1, 500 men surrendered with honours of war,  after a symbolic resistance of nine days (25 August).
According to Dumouriez, the garrison had fired only 5 or 6 artillery shots – disobeying Palhares's prohibition of firing on the enemy – and had suffered only two dead. Having capitulated on condition of not serving against Spain for six months, they were allowed to go free, carry their guns and luggage, and join the Portuguese garrison of Viseu: The Bourbon allies were so amazed with such a hasty proposal for surrender (Palhares would die in a Portuguese prison), that they conceded all demanded.
The capture of Almeida (with 83 canons and 9 mortars) was publicly celebrated in Madrid as a great victory and represented the peak of the initial Spanish predominance. This auspicious beginning led to the impression that the Bourbons were winning the war, but in reality, the occupation of these strongholds would prove to be not only useless, but also harmful to the invaders, as pointed by historian George P. James:
"when these places were taken, the Spanish forces were in a somewhat worse situation than they were before; for penetrating into the wild and uncultivated districts of Beira, with scarcely any road, and, neither abundance of food nor water, they lost more men by disease than all the forces of Portugal would have destroyed ..." 
In addition to this, a new popular revolt exponentially worsened the situation of the invaders.
Like Napoleon during the Peninsular War, the Franco-Spaniards of Aranda would learn in 1762 – at their own expense – that the (brief) occupation of several strongholds, although greatly praised by Spanish historiography, was irrelevant to the ultimate outcome of a war of guerrilla and movements.
The initial Franco-Spanish success in Beira benefitted from the strong popular opposition to the regime of the Marquis of Pombal,  the ruthless Portuguese prime minister; but the massacres and plunder perpetrated by the invaders – especially by the French – soon incurred the peasants' odium. Having penetrated so deeply into the mountainous interior of Portugal, the Franco-Spanish rows find themselves harassed and decimated in ambushes by guerrilleros, who cut their lines of communication and supplies behind them. As Napoleonic general Maximilien Sébastien Foy put it:
"It was nevertheless that indocile host of ordinances rather than the secrets of strategy, which in 1762 paralyzed the Count d'Aranda's Spaniards, and the Prince of Beauvau's Frenchmen. The most skilful general will not long maintain himself in mountains, where the inexhaustible energy of an armed population is interposed between the acting army and its base of operations". — In History of the War in the Peninsula, Under Napoleon.
Several French participants in the campaign stated that the most feared fighters were the guerrilleros of Trás-os-Montes and Beira.  The inhabitants of the province of Beira wrote to the Portuguese prime minister informing him that they did not need regular soldiers, and were going to fight alone.  As explained by Spanish prime minister Godoy:
All the Portuguese, in accordance with the fundamental laws of the country, were soldiers and defenders of the realm until 60 years of age...poured into the roughs, in the heights, in the ravines ... waged a war of guerrilla, causing many more losses on the enemy than the regular [Anglo-Portuguese] troops. The war of positions, marches and counter-marches, imposed upon us by the Count of Lippe, in which we suffered countless losses, was mainly sustained by the armed peasantry. — Manuel Godoy, Prince of the Peace in Memorias.
Sometimes the guerrilleros tortured their numerous prisoners, which in turn generated retaliations upon the civilians, in an endless spiral of violence.  But while the peasant's casualties could be absorbed by their inexhaustible numbers, the same was not true for the invaders. Even in the occupied cities and villages, the populations defied and rebelled against the Franco-Spaniards, according to a letter sent by D`Aranda to Lippe, asking him to put a stop to it.  Many of them were executed.
Instead of trying to defend the extensive Portuguese frontier, Lippe retreated into the mountainous interior to defend the line of the River Tagus, which was equivalent to a forward defence of Lisbon. Lippe’s main goals consisted in avoiding at all cost a battle against such a superior enemy (disputing instead the gorges and mountain passes, while attacking the enemy flanks with small units),  and also preventing the Franco-Spaniards from crossing the formidable barrier represented by the river Tagus. If the Bourbon armies could cross this river, they would reach the fertile province of Alentejo, whose plains would allow their numerous cavalry to reach easily the region of Lisbon. Indeed, immediately after the capture of Almeida, Aranda marched with the intention of crossing the Tagus into the Alentejo at the most propitious point: Vila Velha, where the Spanish army of Philip V of Spain had crossed the river, during the war of the Spanish succession some years before. Lippe, however, anticipated this movement and moved faster. He got to Abrantes and posted a detachment under Burgoynne at Niza and another one under the Count of Santiago near Alvito, to obstruct the passage of the river Tagus at Vila Velha; so that when the invading army came up, they found all these strategic positions occupied (and all boats taken or destroyed by the Portuguese). Therefore, and as Lippe had predicted, the invaders had only two options: return into Spain, to cross the Tagus at Alcántara (which they considered dishonourable since this would imply to withdraw before inferior forces), or go straight to Lisbon through the mountains at the north of the capital, in the "neck" of the "peninsula" containing this city (defined by the river Tagus and the Atlantic).  In order to induce the enemy to choose the second route, Lippe placed some forces in these mountains but left some passages open.  Since Lisbon was the main goal, Aranda advanced, while the allied forces fortified their excellent positions on the heights that cover Abrantes, halfway between Lisbon and the border (the region among the rivers Tagus, Zêzere and Codes). These mountains presented steep slopes on the side of the invaders (acting as a barrier for them), but were very soft on the side of the allies – which allowed them great freedom of movement and facilitated the reinforcements.  Finally, the Anglo-Portuguese army managed to halt the advance of the Bourbon armies toward Lisbon.  It was the turning point of the war.
In order to break this deadlock, the Spaniards went on the offensive towards Abrantes, the allied Headquarters. They took the little castle of Vila Velha (north bank of the Tagus, 3 October 1762) and forced the defiles of St. Simon, near the River Alvito, launching a large force in pursuit of the detachment of Count of Santiago through the mountains. This detachment was very near being entirely cut off, with two Spanish bodies marching upon their front and rear. But la Lippe sent an immediate reinforcement to Count de Santiago, and the combined allied force under Loudoun defeated the chasing Spanish troops at the River Alvito (3 October 1762), and escaped to Sobreira Formosa.  But while, the Spaniards were chasing the Count of Santiago's force through the mountains, they weakened their force in Vila Velha. On 5 October 1762, the Anglo-Portuguese commanded by Lee attacked and completely routed the Spaniards at Vila Velha.  Several Spaniards were killed (including a general, who died trying to rally his troops), and among the prisoners there were 6 officers. 60 artillery-mules were captured, the artillery and magazines destroyed. Moreover, in the very some day (5 October 1762) the Portuguese of Townshend defeated a French force escorting a convoy at Sabugal, capturing a large quantity of precious supplies.
Both armies remained immobilized at Abrantes, facing each other. But while the Anglo-Portuguese continuously reinforced their positions and received provisions,  the Bourbon armies had their line of supply and communication virtually cut off by the armed peasants, militia and ordinances in their rear. Worse than this, they were being starved by a deadly tactic of scorched earth. This tactic would be used again in 1810-11 against the French of Masséna, who, similarly to the invaders of 1762 were stopped in their march on Lisbon, being starved and attacked by guerrillas. As noted by the eminent British military historian Sir Charles Oman:
"Throughout Portuguese history the summons to the levy en masse had always been combined with another measure, from which indeed it could not be disentangled-the order to the whole population to evacuate and devastate the land in face of the advancing enemy. The use of the weapon of starvation... the plan for defeating the enemy by the system of devastation…was an ancient Portuguese device, practised from time immemorial against the Castilian invader, which had never failed of success. (...) When Spain had made her last serious assault on Portugal in 1762... the plan had work admirably..." 
Indeed, the Portuguese soldiers and peasants turned the Province of Beira into a desert: populations abandoned villages, bringing with them everything that was edible. The crops and all that could be useful to the enemy was burned or taken. Even the roads and some houses were destroyed.  
Thus, the exhausted Franco-Spanish army was forced to choose between staying in front of Abrantes and starve, or withdraw, while still possible, closer to the border. 
The allied plan proved almost perfect as it was based in two realities. First, to conquer Portugal the Franco-Spaniards had to take Lisbon. Second, Lisbon could only be attacked from the mountainous North (prevented by the allied defensive system of Abrantes) since Lisbon is protected by the Atlantic Ocean at the West and by the great River Tagus at the South and East, being inside a kind of "peninsula".    It exploited to the full both the Portuguese capital's geographical situation (which could always receive provisions by sea), and the erosion of the Franco-Spanish army through starvation caused by a scorched earth strategy and the collapse of its logistic lines  (attacked by the guerrilla and other irregular forces).
The invading army was suffering terrible losses inflicted by the guerrillas, hunger, desertions, and disease; its situation becoming more and more untenable. Sooner or later, the Franco-Spanish army would have to retreat in a very shattered condition:
"... the embarrassment of the enemy: they were reduced to a forced inaction, while the difficulties of subsistence, desertion and disease, decimated them, and the horses died for want of fodder (p. 47) ... things being in this situation... the enemy... quickly realized that, far from conquering Portugal, this plan would lead his army to ruin (p. 48)." — Allied commander Lippe in Mémoire de la Campagne de Portugal de 1762.
Then Lippe, seeing that the enemy's situation was desperate, completed it with an audacious move,  which decided the campaign: when the Portuguese force of General Townshend - spreading the rumour that was part of a large British force of 20,000 newly landed men- performed an encirclement manoeuvre towards the rear of the demoralized invading army, it withdrew towards Castelo Branco, (from 15 October onwards), which was nearer the frontier and where the new Spanish headquarters were established.  
It was then that the allied army left their defensive positions and pursued the (now diminished)  Spanish army,   attacking its rear, taking many prisoners,  and recovering almost all the towns and fortresses previously taken by the Spaniards -which had given Charles III so many hopes.  On 3 November 1762, during the reconquest of Penamacor and Monsanto, the Portuguese of Hamilton routed a retreating Spanish cavalry force at Escalos de Cima, while the British of Fenton swept another retreating Spanish corps from Salvaterra.  The Spaniards, who had entered Portugal as conquerors, taking provisions by force and torching those villages which refused to supply them,  saw themselves now implacably chased in a devastated enemy territory. The nature of the war had reversed: the hunter had become the prey.
During the retreat, the Franco-Spanish army – weakened by hunger,  disease, and torrential rains – collapsed. Thousands defected (the Portuguese government was offering 1, 600 reis for each Spanish soldier who deserted and 3,000 reis to those who enlisted in the Portuguese Army),  while their stragglers and wounded suffered a slaughter at the hands of the peasants:
"... Yesterday and the day before, I spent passports to 45 [Spanish] deserters; and taking into consideration what they tell us, the Spanish army fell into the abyss; they talk of 7,000 deserters, 12 000 men sick in hospitals, in addition to the many who have died (letter of 27 October) ... and [the number of deserters] would be higher, they say, if they were not afraid of [being killed by] our irregulars (letter of 31 October)." — (letters sent by Miguel de Arriaga – the army’s secretary – to the Portuguese prime minister, Marquis of Pombal, during the chase of the remnants of the Franco-Spanish army).
The Scottish Colonel John Hamilton wrote in a letter dated 24 October 1762, that the army of Charles III was in a "most ruinous shattered condition",  while Lippe would add in his Mémoir (1770) that the Bourbon army was "decimated by starvation, desertion and disease",  his cavalry suffering a "debacle".  The total losses of the Franco-Spanish army during the first two invasions of Portugal -according to a report of British ambassador in Portugal, Edward Hay, to Pitt’s successor, the 2nd Earl of Egremont (8 November 1762)-, was around 30,000 men (half of them deserters, many of whom became prisoners), representing almost three quarters of the initial invading army. 
More recently, French historian Isabelle Henry wrote about these losses: "Disappointed, facing incredible resistance and losing everything in the field, the Spaniards abandoned the fight and left behind twenty-five thousand men ..." 
For its part, the American historian Edmund O'Callaghan estimated that the Spanish army had already lost half of their men even before withdrawing: "Harrassed, dispirited, and reduced to almost one half of their original numbers, the Spanish troops retired within their own frontier". 
Spanish military historian José Tertón Ponce wrote that since the beginning of the first invasion of Portugal up to the middle of the second invasion – immediately before the Bourbon retreat from Abrantes – the invading army had already suffered 20,000 casualties.  There were additional losses during the retreat and third invasion.
Dumouriez, who traveled into Portugal and Spain, collecting testimonies from participants in the invasion of 1762,  reported to Madrid and Paris, in 1766, that the Spaniards had lost 15,000 men during the second invasion of Portugal (province of Beira),  plus 10,000 soldiers during the first invasion of Portugal (Province of Trás-os-Montes),  of whom 4,000 died in the Hospital of Braganza of injuries and sickness.  This chronicler makes no estimate of the Spanish casualties in the third invasion of Portugal (province of Alentejo). The Franco-Spanish disaster was summarily captured in these much quoted contemporary words:
"... the Court of Spain ordered 40,000 men to march into Portugal (p. 247) ... The Spanish forces, when they arrived at the frontier, were reduced to 25,000 men, and never did troops experience a more horrible campaign [2nd invasion]. The sick and the stragglers were almost all of them massacred by the peasants ... the ill-success of the campaign in Portugal; it covered Spain with dishonour, and exhausted her to such a degree as to keep her quiet till the peace (p. 254)." — (Excerpt from the report of French General Dumouriez, who came to Portugal to study the causes of the Franco-Spanish defeat and develop an effective new plan to attack Portugal.  His report was presented to the Spanish king in November 1766 by the French ambassador Ossun, who omitted the passages of the text that mentioned the effectiveness of the Portuguese guerrillas over the Spaniards.   It was also sent to the French foreign minister Choiseul).
Comparatively, during the Napoleonic campaign to conquer Portugal a few years later, in 1810-1811, the French army of Massena lost 25,000 men (of whom 15,000 dead from starvation and disease plus 8,000 deserters or prisoners) to the Anglo-Portuguese of Wellington and guerrillas.  The similarities between the two invasions of Portugal (respectively in 1762 and 1810–11) go far beyond the coincidence of the number of casualties suffered by the invaders in both situations.  Historian Esdaile wrote that Wellington's "...plan [of 1810-11] was one of the most perfect schemes of defence that have ever been devised... It exploited both the Portuguese capital’s geographical situation and the poverty of the Portuguese countryside to the full, whilst at the same time bringing into play traditional responses to invasion in the Form of the ordinances and the devastation of the countryside in a scorched- Earth policy (a similar tactic had actually been Employed against the Spaniards as recently as 1762)." 
Only in the first days of July 1762, the total number of Spanish deserters who had entered the Portuguese army allowed creating 2 new full regiments, besides the many who boarded British and Dutch ships. This suggests a brutal defection rate, since the bulk of defections would only occur from mid-October onwards, during the retreat of the invaders, and most of the deserters who survived the Peasants were not incorporated into the Portuguese army, merely being used as informants or scouts. The Bourbon losses were simply devastating.  Comparatively, the British losses were vastly inferior: fourteen soldiers were killed in combat and 804 men died from other causes, especially disease. 
The tactic of destroying the opponent without fighting and attacking only when he withdraws was the key to victory.
Nothing better symbolizes the Anglo-Portuguese victory than the final conquest of the Spanish headquarters in Castelo Branco itself.  When the allied army began a second encirclement movement to cut off the Spanish forces inside and around Castelo Branco, they fled to Spain, abandoning to their fate all their countless wounded and sick, accompanied by a letter addressed to Townshend, commander of the Portuguese force, in which the Count of Aranda demanded human treatment for their captured men (2 November 1762). 
The number of Spaniards taken can be deduced from a letter sent by the Secretary of the Portuguese army to the Portuguese prime minister (six days before the fall of Castelo Branco, 27 October), stating that according to Spanish deserters, the total number of sick men laying in Spanish hospitals was 12,000.  By the ends of October, the invading army was concentrated almost entirely in the region around Castelo Branco (out of it, there were only little garrisons in the cities of Almeida and Chaves). This number was exceptionally high, since besides the wounded, there were also many sick: the Spanish army, concentrated around Castelo Branco, was suffering a terrible epidemic. This epidemic was transmitted to the Portuguese population itself, when it returned to the city, shortly after the fled of the Spaniards. Thus, the joy of victory was overshadowed by the grief and mourning of many residents. 
American historian Lawrence H. Gipson (winner of the Pulitzer Prize for History):
"Lippe meanwhile had concentrated fifteen thousand British and Portuguese Troops at Abrantes, called 'the Pass to Lisbon'.
With the coming of the autumnal rains and with his army not only ravaged by disease and other ills but greatly reduced as the result of desertions, General Aranda found it impossible to remain in the desolate mountainous country that he was confined. He therefore began to withdraw his 'half-starved, half naked' troops, to Spain, and so precipitously, as to leave, according to reports, his sick and incapacitated behind. (...) The Portuguese war had really ended –and as ingloriously as it had auspiciously begun. But this was not the only humiliation suffered by the Spaniards before the year 1762 came to a close." 
Indeed, the defeat of Spain in Portugal was accompanied and aggravated by setbacks in her empire and in the sea: "In one short year the unfortunate Spaniards saw their armies beaten in Portugal, Cuba and Manila torn from their grasp, their commerce destroyed, and their fleets annihilated". 
Meanwhile, admirers of Aranda anticipated his victory -taken for granted-, such as the humanist and reformer Stanislaw Konarski, who, writing from distant Poland, and ignoring the Franco-Spanish disaster, composed an ode in Latin in his honor, praising the generosity and humanism of the winner of Portugal towards the inhabitants of Lisbon surrendered to his feet. 
The remnants of the invading armies were expelled and chased to the border, and even within Spain itself, as would happen in Codicera, where several Spanish soldiers were imprisoned: "Portugal had not accepted the invitation to join France and Spain in this alliance and the latter powers... invaded Portugal. England sent a fleet promptly to Lisbon with 8,000 soldiers who helped drive the invaders back and followed them into Spain herself...The blows she had received were staggering..." 
At the end of the war, La Lippe was invited by the Portuguese prime minister Pombal to stay in Portugal, in order to reorganize and modernize the Portuguese army (which he accepted).  When Lippe eventually returned to his own country – praised by Voltaire in his famous Encyclopedia, and covered with prestige in Britain, and all Europe – the King of Portugal offered him six cannons of gold (each weighing 32 pounds), a star studded with diamonds, among other gifts, as a sign of gratitude for the man who had saved his throne.  The King determined that, even absent of Portugal, La Lippe retained nominal command of the Portuguese army, with the rank of Marshal General. And he was also given the title of "Serene Highness" (25 January 1763).
On the other hand, British government rewarded him with the title of "honorary Field Marshal".
The third invasion of Portuguese territory was stimulated by the peace negotiations between France and Great Britain and rumours of a general peace (the preliminary Treaty of Fontainebleau was signed on 3 November, one day after the fall of the Spanish Headquarters in Portugal). Indeed, after her defeat in the last invasion, Spain felt compelled to reorganize her troops in order to conquer a portion of Portuguese territory that could be changed by her huge colonial losses at the hands of the British.  This would reinforce her position and bargaining power during the peace talks, which would culminate in the Treaty of Paris, on 13 February 1763.
Since the remnants of the Bourbon troops were settled into winter quarters inside Spain (after crossing the river Tagus at Alcántara), the allied army did the same in Portugal. By then, the French army was practically out of action because in addition to the many dead, deserters and prisoners, there were 3,000 French lying in the hospital of Salamanca. 
Yet Aranda correctly assumed that if he attacked first (before next year's spring, when the new campaign was supposed to start), Portuguese garrisons would be completely taken by surprise. This time, the flatness of the terrain in the province of Alentejo, would give full advantage to the Spanish cavalry, instead of what happened in the two previous invasions. He knew that the Portuguese fortresses were only manned by second line troops (militia), and recent experience proved that siege operations were their Achilles' heel. Besides, the poor state of the Portuguese fortresses in the Alentejo was almost an invitation for invasion: during an inspection to the strongholds of Alentejo, British Brigadier-General Charles Rainsford recommended to remove some of their larger guns to prevent their capture. 
However, Lippe had taken preventive measures by strengthening the garrisons of the Alentejo's fortresses near the border ( Elvas, Marvão, Ouguela, Arronches, Alegrete and Campo Maior), while transferring some regiments from North to South of the riverTagus, in Alentejo, where they continued in winter quarters (but closer to the gravity center of the next campaign). He also created a reserve force consisting in all the British regiments and some Portuguese troops, near Sardoal. At last, some British officers were sent to command Portuguese garrisons in key strongholds: Field Marshal Clark into Elvas, Colonel Wrey into Alegrete, Colonel Vaughan into Arronches, Captain Brown into Marvão, keeping the Portuguese commanders of Ouguela (Captain Brás de Carvalho) and Campo Maior (Governor Marquis do Prado). This set of measures would prove decisive.
For this campaign, the Spaniards assembled three big divisions around Valencia de Alcántara. This time, unlike the two previous invasions, the Spaniards split their army in several corps, with each one attacking one target. A Spanish force of 4,000 or 5,000 attempted to take Marvão with a frontal attack. The terrorized population pressed for surrender, but the firmness of Captain Brown prevailed and he opened fire against the attackers. The Spaniards were defeated with many losses and fled. Another Spanish force of four squadrons attacked Ouguela (12 November 1762), whose walls were ruined. Its tiny garrison, formed by some armed irregulars and fifty riflemen, routed the enemy, who fled leaving many dead behind. The King of Portugal promoted Captain Brás de Carvalho and the other Ouguela's officers to a higher rank. The assault on Campo Maior also failed because the Spanish unit from Badajoz wasn’t supported by the Spanish unit of Albuquerque. The latter fled to Spain when part of the Portuguese garrison of Campo Maior tried to intercept it.
Eventually Lippe mobilized the entire allied army – finishing its winter quarters (12 November 1762) – and moving all units into south of the river Tagus (near Portalegre), as soon as news of the enemy's offensive became known.
The Spaniards were demoralized by these failures: during the two previous invasions not even one stronghold had resisted (a success rate of one hundred percent); while this time not even one fortress had been taken,  giving the Portuguese time to assemble troops. The Portuguese army was now disciplined and well commanded. This renewed army – which initial unpopularity led some men to mutilate themselves to avoid conscription – saw their prestige and numbers skyrocket with volunteers.  On the Contrary, the Franco-Spanish army was greatly diminished after the losses suffered during three failed invasions. Once again – for the third time – the Spanish army was compelled to retreat (15 November 1762) and for the second time, it was chased by Anglo-Portuguese detachments,  which took many prisoners.  A few more prisoners were even taken inside Spain, when the Portuguese garrison of Alegrete, led by colonel Wrey, made a successful raid on Codicera (19 November).
On 22 November 1762, seven days after the beginning of the definitive Spanish retreat from Portugal, and three days after the Portuguese incursion in Spain (Codicera), the commander-in-chief of the Franco-Spanish army ( Count of Aranda) sent Major-General Bucarelli to the Anglo-Portuguese Headquarters at Monforte, with a Peace proposal: the suspension of hostilities. It was accepted and signed 9 days later, on 1 December 1762. 
However, the Bourbon commander would try one last move to save his face: on the very same day Aranda sent a proposal to the Portuguese for the suspension of hostilities (22 November), he also sent a force of 4,000 men to seize the Portuguese town of Olivença. But the Spaniards withdrew as soon as they discovered that the garrison had just been reinforced shortly before. Lippe informed Aranda that such behaviour was odd for someone well-intentioned and eager for peace. (The Spanish commander answered that there had been an error of communication with the leader of that expedition).
A preliminary peace treaty had been signed at Fontainebleau, but the definitive treaty was only signed on 10 February 1763 in Paris,  with the presence of the Portuguese representative, Martinho de Melo e Castro, among all the other. By this treaty, Spain was obliged to return to Portugal the small cities of Almeida and Chaves (in the Hispano-Portuguese frontier), and Colonia del Sacramento in South America (which had been taken to the Portuguese together with part of the Rio Grande do Sul in 1763), besides large concessions to the British: "The Spaniards, having failed the campaign of Portugal, had to return Colonia del Sacramento, renounce claims on their fishing rights in Newfoundland, recognize the legality of the British settlements on the coast of Honduras, cede Florida to England, and confirm all the privileges that British commerce held before the war started." 
Meanwhile, Portugal also captured Spanish territories in South America (1763). The Portuguese won most of the valley of the Rio Negro, in the Amazon Basin, after dislodging the Spaniards from S. José de Marabitanas and S. Gabriel (1763),   where they built two fortresses. The Portuguese, commanded by Rolim Moura, also successfully resisted a Spanish army sent from Santa Cruz de la Sierra (Bolívia) to dislodge them from the right bank of the Guaporé River (Fortress of S. Rosa or Conceição), the "gate" for the gold-rich Province of Mato Grosso (1763).  The besieging Spanish army, reduced to less than half by disease, starvation and desertions, had to retreat, leaving the Portuguese in possession of the disputed territory (both the outcome and strategy resembling the misfortunes of the Spanish army in Portugal). 
This way, the confrontation between Portugal and Spain in South America, during the Seven Years' War, ended in a tactical stalemate. However, while the Spaniards lost to the Portuguese nearly all the territory conquered during the conflict ( Colonia do Sacramento was given back by treaty, and Rio Grande do Sul would be retaken from the Spanish army during the undeclared war of 1763-1777),     Portugal retained all its conquests ( Rio Negro Valley and Guapore’s right bank/ Mato Grosso).
It was a war without formal battles, of marches and counter-marches, and that is why it is called the Fantastic War in Portuguese historiography. It represented a victory of strategy over numbers, since the Bourbon armies failed to reach all their stated goals and had to retreat – with huge casualties – before an advancing and inferior enemy, who chased them out of Portugal. The mountainous nature of the terrain and the collapse of logistic lines, respectively, well used and caused by the allies, were determinant. Eventually, the genius of Count Lippe,  and the discipline of British troops, whose officers managed to reorganize the whole Portuguese army in record time while taking advantage of its bravery,   explain a Portuguese victory that many considered impossible at the time: 
"when Spain declared war against Portugal in 1762, the nominal [Portuguese] army consisted of 17,000 men... of which, not more than half could be mustered, and these without artillery or engineers. The talents of the German Count de La Lippe who commanded them, and the assistance of the British, enabled this force to resist the Spanish army, who retired at the close of the campaign, after sustaining considerable loss as well as from the regulars as the peasants". — W. Bradford in Sketches of Military Costume in Spain and Portugal.
Most decisive of all were the hatred and resistance of rural populations to the foreign invader:    "The Franco-Spanish army, commanded by Prince Beauvau and Count of Aranda, acted softly inside Portugal, who revolted against foreign invasion in the same way that Spain will do in 1808 [against Napoleon], and was aided in its resistance by a body of 8,000 British landed in Lisbon. [The invaders] had to retreat by the valley of the Tagus". 
The Spaniards also made several errors, such as changing plans three times (the main objective being successively Oporto, Lisbon, and Alentejo, during the three invasions) and replacing the army's commander at a critical moment. Their relationship with the French was poor: Aranda even wrote to the Spanish court, complaining of the atrocities committed by French troops against the Portuguese villages. In addition, the large Spanish fleet sent to America not only diverted resources and logistics from the army aimed to conquer Portugal, but also prevented Spain from attacking Portugal by sea.
Besides, the Bourbon numerical superiority was mainly apparent as they had to split their forces in order to sustain the conquered strongholds, look for food, chase the guerrillas, escort supply convoys from Spain, and build roads.  The remaining troops available for main military operations were very few, starved, and demoralized.
According to several contemporaries, the huge human losses experienced by the Spaniards during the invasion of Portugal, contributed to discredit Spain: 
- Contemporary General Dumouriez (French), 1766: "The preservation [independence] of Portugal cost Spain its glory, its treasure, and an army." 
- Contemporary anonymous Spanish author, 1772: "...the discrediting and destruction of a splendid army in the last entry [invasion of Portugal], persuaded Europe that our power was more imaginary than real. With odious comparisons with what we [the Spaniards] were in other times." (in Military-Historical reflections on why Portugal remains independent of Spain and why our wars against it usually end in disgrace, which will continue until we take other dispositions. [in Spanish]). 
- Contemporary Spanish Satire, mocking about the destruction of a Spanish army in Portugal and a navy in Cuba –in just 6 months:
"Through a Compact Family / the sword he drew / thus, it was believed that the world he was going to conquer. / But he sheathed his sword again / having lost a splendid army / an excellent navy, money and a lot of men / and his honor in Havana / in six months alone."  (The invasion of Portugal took six months while the siege of Havana lasted two months).
- José Cornide (Spaniard), who went to Portugal in 1772 to study the reasons of the Franco-Spanish defeat, and elaborated a military report of that country: "The war against the Kingdom of Portugal…its bad outcome, and the loss of a considerable number of troops and even civilians… that were contaminated by the retreating troops (...). Merely in Galicia (about which I can speak with some knowledge) more than 60,000 people were lost as a consequence of the war of 62 ... whenever we adopt... the tactics of the war of 1762, the result will always be so disgraceful as then." 
Far from saving France from defeat, Spain shared it, and indeed made it worse.  However, after the war Spain would commit to peace,  embracing a successful process of reforms and modernization.  
After the end of the Seven Years' War, there was a war council in Spain to judge the military leaders involved in the fall of Havana at British hands, mainly Juan de Prado y Portocarrero (governor of Cuba) and the Marquis of the Royal Transportation. The Count of Aranda was the President of this council. The punishments were generally very severe, and Aranda was particularly active asking inclusively the death sentence for the former Viceroy of Peru, Count of Superunda– whose only crime had been to be in the wrong place at the wrong time (he was returning to Spain after serving the Crown in Peru for 16 years, when he was caught in the Havana's siege).
The devastating defeat caused great commotion in the Spanish public opinion,  who demanded scapegoats. But, ironically, it would be the loser of the Portuguese campaign of 1762 who would judge the loser of Cuba. Spanish historian José de Urdañez pointed out that:
"as the best biographers of the Aragonese count [Aranda] have explained, 'under the cover of rigor, the material and moral failure that this war had been to Spain was camouflaged before the people.' (...). However, it was still amazing that the leader of the defeated army in Portugal was the fierce accuser of the defenders of Havana..." — In Víctimas Ilustradas del Despotismo. El Conde de Superunda, Culpable y Reo, ante el Conde de Aranda .
Curiously, the Franco-Spanish invasion of Portugal is almost a forgotten episode in Portuguese History text books. And for Portuguese literature, it is like a blind spot (with a few exceptions: Hélia Correia's "Lillias Fraser" and Mário de Carvalho's "A paixão do conde de Fróis").
However, in English literature, there is at least a book on the subject: Absolute honour, whose hero is an Englishmen (Jack Absolute) that lives adventures during the Bourbon invasion of Portugal in 1762. Naturally, and for understandable reasons, this campaign is also almost absent from Spanish literature. There is, nevertheless, a high qualified exception -the great Novelist and Dramaturge Benito Pérez Galdós, who wrote a tale about the battle of Bailén, where a personage, D. Santiago Fernández, describes sarcastically his participation in the campaign of 1762, fiercely defending his master, the marquis of Sarria: "... There was no other Sarria born after Alexander the Macedonian (...). That was a great campaign, yes sir; we entered Portugal, and although we had to withdraw shortly after, because the English appeared before us (...). The Marquis of Sarria was a supporter of the Prussian tactic, which is to be quiet and wait for the enemy to advance wildly, thus rapidly being tired and defeated. In the first battle fought with the Portuguese villagers, everyone began to run when they saw us, and the general ordered the cavalry to take possession of a herd of sheep, which was achieved without bloodshed." 
The Spanish invasion of Portugal in Europe (main theater of the war, which absorbed the lion's share of the Spanish war effort) was followed by a Spanish invasion of Portuguese territories in South America (a secondary theater of the war). The first ended in disaster, the second had a mixed result.
- Uruguay: the Spanish Cevallos expedition (3,900 men)  was successful. In present-day Uruguay, they captured Colónia do Sacramento (with 767 defenders),  where 26 British ships with a valuable cargo were taken. When a small Anglo-Portuguese fleet under McNamara tried to retake Colonia do Sacramento in 1763, it was beaten off: The Portuguese didn’t lose any ship, but the British lost their main ship, the Lord Clive (272 dead) and suffered 105 dead in the ship Ambuscade.
- Rio Grande do Sul (South Brazil): Cevallos advanced North with a Hispano-Indian army of 6,000 men and reached an even greater victory when he conquered most of the vast and rich territory of the so-called “Continent of S. Peter” (the present day Brazilian state of Rio Grande do Sul), where the Portuguese had only up to 1,000 men (soldiers and militia).  São José do Norte and the capital – S. Pedro do Sul- were abandoned without a fight.
However, the Spaniards were defeated by the Portuguese at the battle of Santa Bárbara (1 January 1763),  when an invading army of 500 Spaniards and 2,000 Indians,  in cooperation with Cevallos, tried to conquer Rio Pardo, almost the only remaining Portuguese territory in Rio Grande do Sul: seven cannons,  9,000 heads of cattle and 5,000 horses were captured.  This huge territory would be completely retaken by the Portuguese during the so-called “deaf war” (1763-1777).    
- Rio Negro (Amazonia, North Brazil): Portugal conquered the valley of the Rio Negro (1763), in the Amazon Basin, after dislodging the Spaniards from Marabitanas and San Gabriel (1763). 
 There they raised two fortresses, using Spanish cannons.
- Mato Grosso (western Brazil): the Portuguese, commanded by Rolim Moura, also successfully resisted a Spanish army sent from Santa Cruz de la Sierra (Bolívia) to dislodge them from the right bank of the Guaporé River (Fortress of S. Rosa or Conceição), the gate for the gold-rich Province of Mato Grosso (1763), which the Spanish crown intended to recover. The Portuguese not only used biological warfare (according to the Spanish commander, the Governor of Santa Cruz de la Sierra) but also captured and occupied - until the end of the war - the reductions of S. Miguel and S. Martin, which were main sources of Spanish supply and were located on the Spanish side of the river Guaporé (left bank).  Thus the besieging Spanish army, reduced to less than half by disease, starvation and desertions, had to retreat, leaving the Portuguese in possession of the disputed territory.  Rolim de Moura would be rewarded for his victory with the Viceroyalty of Brazil. A second Spanish attack 3 years after the end of the seven years' war, failed miserably again (1766).
This way, if the confrontation between Portugal and Spain in South America, during the Seven Years' War, ended in a tactical stalemate, it represented also a Portuguese strategic victory in the short run: the Spaniards would lose to the Portuguese nearly all the territory they had conquered during the conflict ( Colonia do Sacramento was given back by the treaty of Paris, which ended the war, and Rio Grande do Sul would be retaken from the Spanish army during the undeclared war of 1763-1777),     while Portugal retained all its conquests ( Rio Negro Valley and Guapore’s right bank/ Mato Grosso).
- "The Iberian war of 1762 is an anomaly within the Seven Years' war. Yet its less-than dramatic conduct should not overshadow its importance. As part of a larger campaign it was born of an illusion imagined by the Bourbon powers. ... These illusions... set the stage for the war’s final Bourbon disaster. ( p. 429) ... A reported 4,000 Spanish troops died in the hospital at Bragança, and it was estimated that of the 40,000 who invaded Portugal... only 25,000 returned the following spring... Bourbon casualties mounted because the Portuguese peasantry waged a relentless war of revenge against deserters and retreating soldiers who they captured and massacred in large numbers. ( p. 452) The Portuguese campaign, indeed the entire Spanish war, lay in ruins." ( p. 521)”. In Danley Mark and Patrick Speelman – The Seven Year’s War: Global Views, Brill, 2012, chapter 16 (pp. 429-460).
- "... three Spanish armies invaded Portugal with the plan to converge on Lisbon and Oporto…by autumn, the remnants of Spain’s armies had fled from Portugal". In Nester, William – The First Global War: Britain, France, and the Fate of North America, 1756-1775, USA, 2000, p.218.
- "The last best hope for France and her allies in 1762 consisted in the entry of Spain – by all standards a colossal disappointment, involving a failed invasion of Portugal and the loss of major colonial bases at Havana, Cuba, and Manila, ( p. 88)... the failure of the Spain’s operations in Portugal, a setback that greatly diminished the war fervour of Charles III and helped promote the cause of peace."( p. 219) In Schumann, Matt; Schweizer, Karl – The Seven Years War: A Transatlantic History, Routledge, 2008.
- "In Europe, Spanish arms were no more successful [than In Havana]. The invasion of Portugal, planned as a diversion to assist France, proved an unexpected failure. In October 1762 Charles III capitulated. (...) Spain had been dragged into the war in the interests of France, had suffered serious losses and was now being urged to make a hasty peace, also in the interests of France." In Parry, John Horace – "The Spanish Seaborne Empire", University of California Press, 1990, p. 303
- "Effort of the Bourbon powers to set up the beginnings of a 'continental system' by sending a summons to Portugal to close her ports to British ships and exclude Englishmen from Brazil trade. But the Portuguese minister, the Marquis of Pombal, refused, and with the assistance of Count Lippe and the English General Burgoyne broke the offensive of the Spanish invading army. D'Aranda, the Spanish General, was forced to retreat in disgrace. With the utter failure of the Spanish war machine everywhere, all the hopes which Choiseul [French Foreign Minister] had placed on the Spanish alliance vanished. 'Had I know', he wrote, 'what I now know, I should have been very careful to cause to enter the war a power which by its feebleness can only ruin and destroy Fance' ". In Dorn, Walter – Competition for Empire, 1740-1763, p.375.
- "…one can understand Choiseul's disappointment. The Spanish army had failed miserably in Portugal, and the Spanish navy performed no better ( p.224)… Nowhere was Spanish overconfidence and inexperience more apparent than in the Portuguese campaign." ( p. 221)" In Dull, Jonathan – The French Navy and the Seven Years' War, University of Nebraska, 2007, pp. 221-224.
- "Defeat seemed to be ever present and everywhere for the Bourbon kings. In this unfortunate situation the only recourse for the Franco-Spanish alliance was to sue for peace... In the summer of 1762, as the Spanish army suffered humiliation in Portugal and Cuba, diplomatic negotiations resumed..." In GOLD, Robert- Borderland empires in transition, Southern Illinois University Press, 1969, p. 14.
- " ...the year of 1762 was terrible for the arms of France and Spain which only experienced defeats in Germany and at Portugal, whose King, Louis XV and Charles III wanted to force to join their alliance [against Great Britain]." In Terrage, Marc de Villiers du (1904). Les dernières années de la Louisiane française (in French), E. Guilmoto, p. 151.
- "The unfortunate campaign of Portugal and the disasters of Havana and Manilla left the Spanish armed forces a bitter feeling that it would take a long time to dissipate. 'it is impossible for a disgraceful war to produce an honorable peace.' sadly wrote the Spanish Chief minister Ricardo Vall." In Alonso, José Ramon – Historia Política del Ejército Español, Editora Nacional, 1974, p. 51.
- "On every side the Spaniards were worsted, and in a short time, such was the vigour with which the operations were conducted, they were driven before the victorious allies, and compelled to evacuate the Portuguese territories". In Carnota, John Smith A. – The Marquis of Pombal, 2nd edition, Longmans, Green, Reader, and Dyer, London, 1871, p. 189.
- "Animated by the genius of the Count of Oeyras, afterwards distinguished by the title of Pombal, inspirited by the vigorous succours of the English, and directed by the military skill of Count de la Lippe, the Portuguese made an unexpected resistance, and compelled the combined forces of the French and Spaniards again to evacuate the country." In Coxe, William – "History of the House of Austria", Vol. III (3rd edition), London, 1847, p. 432.
- " ...Portugal, whose war was bloody, and in the end, fatal to the Spaniards, who had finally to abandon that country." In Losada, Basilio S. Castellanos – Historia de la vida de D. José Nicolás de Azara, Vol. I, Madrid, 1849, p. 25.
- "This disavowal is the consequence of the double humiliation that Spain has just undergone on the international scene, with the defeat of its army in Portugal and with the capture of Havana by the English. Confining itself to a disaster, the Seven Years' War marks a major shift in the Chalrles III policy ... " In Glesener, Thomas- L´Empire des Exilés: Les Flamands et le Gouvernment de l´Espagne au XVIIIº Siècle., Casa de Velázquez, Madrid, 2017, p. 268.
- "The subsequent expedition against Havana…the loss of Manila in the Philippines and her defeats in Portugal, dealt Spain’s prestige a blow from which it never recovered." In The Mariner’s Mirror, Vol. 68-69, Society for Nautical Research, UK, 1982, p. 347.
- "... with the help of a small British expeditionary force, Portugal repulsed the Spanish attack." In Dull, Jonathan- The Age of the Ship of the Line: the British and French navies, 1650-1851. University of Nebraska Press, 2009, p. 88.
- "As for Spain, the expulsion of her troops from Portugal, the loss of Cuba and the Philippines, twelve ships and more than 100 million, made her deeply regret her involvement in the war." In Roujoux and Alfred Mainguet – Histoire d`Angleterre (in French), Vol. II, Paris, Charles Hingray, Libraire-Éditeur, 1845, p. 404.
- "Portugal had not accepted the invitation to join France and Spain in this alliance and the latter powers …invaded Portugal. England sent a fleet promptly to Lisbon with 8,000 soldiers who helped drive the invaders back and followed them into Spain herself... The blows she had received were staggering..." in Hart, Francis Russel – The Siege of Havana: 1762, Houghton Mifflin, 1931, p. 52
- "…the annoyance given by the peasantry, checked the progress of the Spaniards. Accordingly …the invaders retired within their own frontiers, evacuating all their conquests. This campaign constituted nearly the whole of the Spanish share of the Seven Years' War in Europe." In Busk, M. M. – The History of Spain and Portugal from B.C. 1000 to A.D. 1814, Vol. 25, Baldwin and Cradock, Paternoster-Row, London, 1833, page 204.
- "As soon as the enemy began to retire upon Castello Branco, Major-general Fraser was sent…to attack his rear…General Burgoyne advanced [he reoccupied Vila Velha de Ródão]… while General Townsend occupied Penamacor and Monsanto…the Count d`Aranda kept his Head-quarters at Castello Branco… Lippe, with his small army, determined to attack this force…and Aranda retreated at leisure, leaving his sick and wounded in the hospital at Castello Branco, with a letter, recommending them to the attention of the allied army…On the 15th of November, therefore, the whole of their force retired into Spanish Estremadura…and Portugal, with the exception of Almeida and Chaves, was freed from the enemy." In The Royal Military Chronicle, vol V, London, 1812, pp. 52, 53.
- Eduard Hay, British ambassador in Portugal (letter to the 2nd Earl of Egremont, 8 November 1762) reported a total of 30,000 Franco-Spanish casualties during the first two invasions of Portugal (half of them deserters, many of whom became prisoners), representing almost three quarters of the initial invading army. See British Scholar C. R. Boxer in Descriptive List of the State Papers Portugal, 1661-1780, in the Public Record Office, London: 1724-1765, Vol II, Lisbon, Academia das Ciências de Lisboa, with the collaboration of the British Academy and the P.R.O., 1979, p. 415. See also COSTA, Fernando Dores- Nova História Militar de Portugal , Círculo de Leitores, Vol. II, Coordinator: António Hespanha, 2004, p. 358, footnote 280.
- A contemporary anonymous Spanish author, wrote in 1772 a reflexion on the causes of the "disgraceful" outcome of the Spanish invasion of Portugal (1762): "...the discrediting and destruction of a splendid army in the last entry [invasion of Portugal], persuaded Europe that our power was more imaginary than real. With odious comparisons with what we [the Spaniards] were in other times." In Military-Historical reflections on why Portugal remains independent of Spain and why our wars against it usually end in disgrace, which will continue until we take other dispositions. [in Spanish]). In the Original: Reflexiones Histórico-Militares que manifiestan los Motivos Porque se Mantiene Portugal Reino Independiente de España y Generalmente Desgraciadas Nuestras Empresas y que Lo Serán Mientras No se Tomen Otras Disposiciones , Borzas, 28 November 1772; cited in In José Tertón Ponce – La Casaca y la Toga: Luces y sombras de la reforma militar en el reinado de Carlos III Archived 2014-07-07 at Archive.is, Institut Menorquí d'Estudis, Mahón, 2011, La campaña de Portugal en 1762, pp.11-21, p.21.
- Reports sent by Miguel de Arriaga (the army’s secretary) to the Portuguese prime minister, during the chase of the remnants of the Franco-Spanish army: "... Yesterday and the day before, I spent passports to 45 [Spanish] deserters; and taking into consideration what they tell us, the Spanish army fell into the abyss; they talk of 7,000 deserters, 12 000 men sick in hospitals, in addition to the many who have died (letter of 27 October)... and [the number of deserters] would be higher, they say, if they were not afraid of [being killed by] our irregulars (letter of 31 October)." In SALES, Ernesto Augusto- O Conde de Lippe em Portugal, Vol 2, Publicações de Comissão de História Militar, Minerva, 1936, page 29
- Historian Lawrence H. Gipson uses the expression "the disintegration of the Spanish army" (see The British Empire before the American Revolution: the great war for the Empire: the culmination, 1760-1763, Knopf, 1954, p. 260); while Portuguese historian Fernando Dores Costa wrote about the Spanish army’s "spectrum of decomposition" (see Nova História Militar de Portugal, vol. II, Círculo de Leitores, Coordinator: António Hespanha, 2004, p. 358, footnote 280.). Also Portuguese historian Nuno Monteiro wrote that "... although there have been no battles in this strange war, severe losses occurred [on the Spanish side]" (see D. José: na sombra de Pombal, Temas e Debates, 2008, p. 198).
- "The army was in no better shape. Only 8,000 effective [Portuguese] soldiers stood in the face of the coming Spanish onslaught. They wore 'rags and patches' and begged in the streets, as they received little or no pay from the central government." In Speelman, Patrick and Danley, Mark – The Seven Year’s War: Global Views, 2012, p. 436.
- Between 7,000 and 8,000 Portuguese in Chagas, Pinheiro- História de Portugal, vol. VII, Lisboa, 1902, p. 40.
- "The British troops which embarked for Lisbon under their veteran commander consisted of 7, 104 officers and men of al arms [official figures when boarding in Britain]. This force had been dispatched In consequence of the threatening attitude of France and Spain towards Portugal, whose monarch had declined to enter into an alliance with the above two powers in order to 'curb the pride of the British nation which aspired to become despotic over the sea'." In Dalton, Charles- George The First's Army, 1714-1727, Vol. II, 1912, p. 31
- "All told the British forces in Portugal numbered roughly 7,000 men." In Speelman, Patrick and Danley, Mark – The Seven Year’s War: Global Views, 2012, p. 440.
- Selvagem, Carlos- Portugal Militar (in Portuguese), Imprensa Nacional-Casa da Moeda, Lisboa, 2006, p. 475.
- Selvagem, Carlos- Portugal Militar (in Portuguese), Imprensa Nacional-Casa da Moeda, Lisboa, 2006, p. 476.
- "This operation was without doubt the greatest mobilisation of troops on mainland Spain throughout the whole eighteenth century, and the figures themselves bear witness to the government's interest in the operation…and meant leaving the rest of mainland Spain largely unguarded…by way of comparison, the battle of Almansa of 1707…involved a Spanish-French army of over 25,000 men…while the famous attack on Algiers in 1775 involved a mobilisation of little more than 19,000 infantry and cavalry men..." in Enciso, Agustín González (Spanish) – "Mobilising Resources for War: Britain and Spain at Work During the Early Modern Period", Eunsa, Ediciones Universidad de Navarra, S.A., Spain, 2006, p. 159, ISBN 9788431323844.
- “In this offensive would participate the most distinguished of the Bourbon army, newly reformed; and, as officers, the brightest students graduated from the modern military academies established a few decades ago in Barcelona, Segovia and Madrid, following the dictates of the enlightened science of the time (…).” See «De Espanha, nem bom vento nem bom casamento». La guerra como determinante de las difíciles relaciones entre las dos Coronas Ibéricas en la Península y en América. 1640-1808 (in Spanish, pp. 29-111) in Anais de História de além-mar, Vol X, Juan Marchena Fernandez, 2009, Anais de História de além-mar, p. 71.
- Letter XLIV, from a British captain: "Lisbon, 1779... Dear brother (p. 409)... after comparing every thing, after visiting the frontiers of the two kingdoms, (as I have endeavoured to do with something of a critical eye) to me it appears that a successful invasion of Portugal from Spain, at least as circumstances at present stand, would be so exceedingly probable, or rather certain, that I find it very difficult to account for the miscarriage of their last attempt upon it in 1762 ( page 415)... an army consisting of at least 30,000 men, with 10 or 12,000 French auxiliaries, and a large park of artillery…collected at a great expense from Catalonia and the farthest parts of the Kingdom…establishing large magazines in different parts of the frontiers…it is astonishing that with such a shadow of an army to oppose them (p. 416)...", in Costigan, Arthur W. – Sketches of Society and Manners in Portugal, vol. II, London, 1787, pp. 409-416.
- 30,000 Spaniards, according to a letter of Charles III to Count of Gazola in December of 1761 plus 10,000 French in 12 battalions who joined them in 12 June 1762. All these informations in Mourinho, António- Invasão de Trás-os-Montes e das Beiras na Guerra dos Sete Anos Pelos Exércitos Bourbónicos, em 1762, através da Correspondência Oficial (in Portuguese)..., Series II, Vol 31, Anais da Academia Portuguesa de História, Lisboa, 1986, pp. 380 and 395.
- "A Campaign won without the major casualties of battle or incurring many losses other than those of sickness." In Journal of the Society for Army Historical Research, vol. 59, London, 1981, p. 25
- "British casualties were light overall - there were fourteen combat deaths compared to 804 from other means..." In Speelman, Patrick and Danley, Mark – The Seven Year’s War: Global Views, 2012, p. 448
- "Disappointed, facing incredible resistance and losing everything in the field, the Spaniards abandoned the fight and left behind twenty-five thousand men ..." In Henry, Isabelle – Dumouriez: Général de la Révolution (1739-1823), L'Harmattan, Paris, 2002, p. 87.
- In Morell, Thomas – Studies in History, vol. II, London, 1821, p. 373.
- "Boscawen had defeated the French fleet off the Portuguese coast. The French commander took refuge in Lagos after losing five of his ships on the coast of the Algarve. The French at once began to demand satisfaction, and Pitt sent Lord Kinnoull on a special mission to Lisbon to offer apologies." In Livermore, H. V. – A New History of Portugal, Cambridge University Press, London, 1969, p. 234.
- José Hermano Saraiva (coordinator) – História de Portugal, vol. VI, Quidnovi, 2004, p. 63.
- "France’s Foreign Minister, the Duc de Choiseul, had pressured Charles III of Spain to declare war against Britain, even as he was beginning secret negotiations with London to end the fighting". In York, Neil Longley – Turning the World Upside Down: The War of American Independence and the Problem of Empire, Praeger, London, 2003, p. 33.
- "Spanish invasion of Portugal, an effort to block the British in Europe, also resulted in defeat for Spain." In Altagracia Ortiz – Eighteenth Century Reforms in the Caribbean, Fairleigh Dickinson Univ Press, 1983. p. 216, footnote 16.
- "... in September , English naval forces intercepted official correspondence from Spain and learned that Madrid would enter the war if no peace were arranged by May 1762. On January 2, 1762, England declared war preemptively against Spain..."; in Stein, Stanley and Stein, Barbara – Apogee of Empire: Spain and New Spain in the Age of Charles III, 1759-1789, Johns Hopkins University Press, 2004, chapter The Trauma of Havana, 1762-1765.
- "A family compact between the two crowns was signed in August 1761 guaranteeing their mutual possessions; a 'secret clause' further stipulated that if France was still at war with Britain in May 1762 Spain should declare war on Britain." In Pack, S. W. – Sea Power in the Mediterranean: A Study of the Struggle for sea power in the Mediterranean from the Seventeenth Century to the Present Day, Arthur Barker Limited, 1971, p. 68.
- In Carnota, John Smith A. – The Marquis of Pombal, 2nd edition, Longmans, Green, Reader, and Dyer, London, 1871. p. 187.
- Carvalhosa, Manuel F. Barros (Viscount of Santarém) – Quadro Elementar das Relações Políticas e Diplomáticas de Portugal, Tome VI, Paris, 1850, p. XVI.
- "One of the main aims of the two great Bourbon powers, in the making of the Family Compact, had been to attack Portugal, in order either to compel England to despatch a large part of its troops to that country, or to take possession of it…"; in Philippson, Martin – The Age of Frederick the Great, vol. XV, Lea Brothers and & company, Philadelphia, 1905, p. 103.
- Livermore, H. V. – A New History of Portugal, Cambridge University Press, London, 1966, p. 232.
- Clark, Edward – Letters concerning the Spanish nation, London, 1763, p.353.
- Livermore, H. V. – A History of Portugal, Cambridge University Press, London, 1947, p. 359.
- According to Dumouriez in An Account of Portugal, as it Appeared in 1766 to Dumouriez, Lausanne (1775), and London (1797), p. 103.
- According to Dumouriez in An Account of Portugal, as it Appeared in 1766 to Dumouriez, Lausanne (1775), and London (1797), p. 244.
- Azevedo, J. Lúcio de – O Marquês de Pombal e a sua época, 2nd edition, Annuário do Brasil, Rio de Janeiro, p. 237.
- In Dellon, Gabriel (and other authors)– Portugal nos Séculos Dezassete e Dezoito: Quatro Testemunhos, Lisóptima Edições, 1989, p. 157. (in Portuguese).
- O’Callaghan, Edmund Bailey – Orderly Book of Lieut. Gen. Burgoyne, New York, 1860, Introduction, p. XIV.
- "Portugal refused [to submit to the ultimatum], whereupon Spain and France said they would invade Portugal to free her from 'the heavy shackles of Britanic dominion' ". In Shaw, L. M. – The Anglo-Portuguese alliance and the English merchants in Portugal, 1654-1810, Ashgate, 1998, p. 193.
- "Madrid believed a show of force on the border might compel Oeyras [the Portuguese prime minister] to cave to Bourbon demands; so the army was given light provisions to hasten its arrival. It was a futile gesture. In May the under-supplied expeditionary army invaded and advanced towards Oporto. A column of 22,000 men under Commander-in-Chief Nicolás Carvajal y Lancaster, Marquis de Sarriá, crossed into Northeast Portugal as 'friends' …" In Speelman, Patrick and Danley, Mark – The Seven Year’s War: Global Views, 2012, p. 438.
- "The Province was absolutely defenceless without soldiers, arms, powder, ball or provisions, and it was impossible to paint the scandalous conditions of the defences." In Francis, Alan David – Portugal 1715-1808, Tamesis Books Limited, London, 1985, p.150.
- Dumouriez, Charles – An Account of Portugal, as it Appeared in 1766 to Dumouriez, Lausanne (1775), and London (1797), p. 249.
- Francis, Alan David, Portugal 1715-1808, 1985, p. 150.
- "Lack of supplies slowed and then distracted them. Wishing to win over popular sentiment, Sarriá at first paid the Portuguese double for provisions. He had assumed wrongly that Portugal could provide all that was required, thus allowing war to feed war. When the necessary supplies did not materialize he exacted forced contributions from the countryside, and this, along with a native hatred of the Spanish, triggered a general peasant uprising..." In Speelman, Patrick and Danley, Mark- The Seven Year’s War: Global Views, 2012, p. 439.
- "Both sides relied extensively on foreign troops and officers, though Portuguese popular opposition to the Spaniards proved decisive in places, especially in the North." In Maxwell, Kenneth – Pombal, Paradox of the Enlightenment, University Press, Cambridge, 1995, p. 113.
- Martin, Benjamin – Miscellaneous Correspondence, vol. IV, London, 1764, p. 904.
- See Dumouriez, Charles – An Account of Portugal, as it Appeared in 1766 to Dumouriez, Lausanne (1775), and London (1797), p. 18.
- Lafuente, Modesto – Historia General de España, tome XX, third part, 8th book, Madrid, 1858, p. 55.
- Monteiro, Nuno Gonçalo – D. José: na sombra de Pombal, Temas e Debates, 2008, p. 198.
- "Spain now controlled the entire province of Tras-os Montes... the way to Oporto lay open and a general alarm engulfed Portugal... the Governor of Oporto…received orders to retreat towards Lisbon if the Spanish advanced... English merchants there began to evacuate (...). All that was left to the Spanish was to cross the Douro River... Charles O’Hara led a rag-tag peasant band of 1,500 angry peasants, most of who wielded implements, and repulsed the 5,000-strong Spanish force. This action upset the Spanish plan to cross the Douro... similar partisan activity repulsed a Spanish advance on Almeida on 25 May. The rest of the Portuguese population simply deserted their villages and fled to the mountains.... the Spanish thrust had been parried. Sarria’s offensive grounded to a halt. 'Small war' had trumped the big battalions." In Speelman, Patrick and Danley, Mark – The Seven Year’s War: Global Views, 2012, p. 439.
- The British Chronologift: "Battle, at the river Douro, when the Portuguese defeated the Spaniards, May 25, 1762". London, 1789, Index to vol.III (1748-1762), p. 482.
- Green, William – Chronological History of the Reign of George the Third, London, 1826, page 10: "The French and Spaniards enter Portugal; reinforcements sent to assist the Portuguese. May 25. The Portuguese beat the Spaniards on the River Douro."
- "The French officer, Dumouriez, who visited Portugal in 1766 with the express object of studying the campaign and the reasons for Spanish failure…" In Journal of the Society for Army Historical research, vol. 59, London, 1981, p. 25.
- Dumouriez, Charles – An Account of Portugal, as it Appeared in 1766 to Dumouriez, Lausanne (1775), and London (1797), chapter 3, p.p 18-19.
- Dumouriez, Charles – An Account of Portugal, as it Appeared in 1766 to Dumouriez, Lausanne (1775), and London (1797), Chapter VIII, p. 249.
- In Le Nouvelliste Suiss, july 1762, Newchatel, p. 277.
- "[Province of] Beira. Almeida, June 12, …the Enemy [Spaniards], to the number of eight thousand has entered the frontier… several parties have rallied forth from the camp, and had pillaged the villages upon that frontier, and had not even spared the churches; but that these parties had been driven back by the Portuguese militia, who had killed and taken prisoners upwards of two hundred Spaniards;" in Martin, Benjamin – Miscellaneous Correspondence, vol. IV, London, 1764, p. 904.
- "Extract of a letter from Lisbon, May 29. (…) at Almeida, which is a place of some strength, having six regular bastions, and three half moons besides a well-built fort with four bastions; they have received a check, and in their attempt to take it by a coup the main, have lost, it is said, 600 men, (...)" Published in The London Chronicle for The Year 1762, Vol. XII (from June 30, to December 31), number 86 (from June 29 to July 1), p. 6.
- "There are letters by the... man of war arrived at Plymouth from Oporto, dated the 11th of June  , which say, that 4 000 regulars and 6 000 of the militia, were arrived at that place... the Spaniards hearing of their arrival at Oporto, and that the Portuguese expected every hour to receive a reinforcement of horse and foot, have declining penetrating any further into that part of the country; (...). Other letters say, that 14,000 Portuguese, 7,000 of them regulars... were marched beyond Oporto, and had blocked up all the defiles and passes leading to Spain; so that the Spaniards must either starve or retire. It is added, that the later are already in great want of provisions, and that vast numbers desert daily to the Portuguese troops at Oporto". In The London Chronicler, or Universal evening Post (for the year of 1762), vol. XII, nr. 86 (from Tuesday, June 29, to Thursday, July 1, 1762), London, p. 6.
- In The London Chronicler, 1762, (from 29 June to 1 July).
- "The Spanish failure in 1762 to exploit their early successes by a march to capture Oporto , the major town in Northern Portugal, proved operationally decisive." In Black, Jeremy – European Warfare in a Global Context, 1660-1815, Routledge, 2007, p. 41.
- Dumouriez, Charles – An Account of Portugal, as it Appeared in 1766 to Dumouriez, Lausanne (1775), and London (1797), chapter 3, p. 20.
- Serrão, Joaquim Veríssimo – História de Portugal: O Despotismo Iluminado (1750-1807), vol. VI da História de Portugal, Editorial Verbo, 1977, p.61.
- Serrão, Joaquim Veríssimo – História de Portugal: O Despotismo Iluminado (1750-1807), vol. VI da História de Portugal, Editorial verbo, 1977, p.61.
- Ponce, José Luis Terrón – La Casaca y la Toga: Luces y sombras de la reforma militar en el reinado de Carlos III Archived 2014-07-07 at Archive.is, Institut Menorquí d'Estudis, Mahón, 2011, Chapter 2: La campaña de Portugal en 1762, pp.11-21 Archived 2014-07-14 at the Wayback Machine., p. 13.
- "This province [of Trás-os Montes] is not worth an attack in a war between Spain and Portugal; it is even dangerous for the Spaniards to penetrate into it, as they found to their cost in the late war; 40,000 men advanced to Chaves, Bragança and Miranda…and about a fourth of their number died there..." In Dumouriez, Charles – An Account of Portugal, as it Appeared in 1766 to Dumouriez, Lausanne (1775), and London (1797), p. 20.
- "…it was found that the Marquis of Marialva and the Field-Marshals Count of Angeja, Count of Arcos and José Leite de Sousa were approaching Lamego with 7 regiments, British forces and militias. If this force entered Trás-os Montes, it could divide the two wings of the Spanish army – that trying to reach Oporto through the mountains, and that trying to reach the left bank of the Douro – which was a huge risk." in Barrento, António – Guerra Fantástica, Portugal, o Conde de Lippe e a Guerra dos Sete Anos, Tribuna, Lisboa, 2006, pp. 55-56.
- "(…). In fact they made a very good effort; the Trás-os Montes invasion was turned back" ( p. 150) … On the South Bank [of the river Douro] O’Hara was at Lamego, where a considerable Portuguese regular force was mobilizing, and in the mountains near Vila Real the enemy were afraid of being cut off by the auxiliaries there and found it prudent to retire. ( p. 151)" in Francis, Alan Davis – Portugal 1715-1808, Tamesis Book Limited, London, 1985.
- "The English, by means of their officers, had so skilfully directed the rising and resistance of the brave inhabitants of the mountains of Trás-os-Montes, which had been occupied by the Marquis de Sarriá, that he was compelled to evacuate Braganza, Miranda, Chiaves and Moncorvo at the very time at which Count William arrived." In Chlosser, Friedrich (translated by D. Davison,M. A.) – History of the Eighteenth Century and of the Nineteenth Till the Overthrow of the French Empire (1843), Vol. IV, Chapman and Hall, London, 1845, pp. 252-53.
- "…in the meanwhile, Sarriá's army continued retreating From Torre de Moncorvo, Mogadouro, Mirandela and Braganza … hastily reaching Zamora [Spain] on 3, 4 and 7 July, toward Ciudad Rodrigo." In Academia Portuguesa da História- Anais, 1986, p. 396.
- “In this offensive would participate the most distinguished of the Bourbon army, newly reformed; and, as officers, the brightest students graduated from the modern military academies established a few decades ago in Barcelona, Segovia and Madrid, following the dictates of the enlightened science of the time. (…) Departing from Zamora, the Spaniards took the cities of Bragança, Chaves, Miranda and Moncorvo Fort in 1761, although the Portuguese counterattacks made them retreat.” See «De Espanha, nem bom vento nem bom casamento». La guerra como determinante de las difíciles relaciones entre las dos Coronas Ibéricas en la Península y en América. 1640-1808 (in Spanish, pp. 29-111) in Anais de História de além-mar, Vol X, Juan Marchena Fernandez, 2009, Anais de História de além-mar, p. 71.
- Masséna's Aide-de-camp (1810), cited in Pecchio, Giuseppe – Lettres Historiques et Politiques sur le Portugal, 1830, p. 303.
- "As the first stores arrived at the end of April, and the first [British] troops a few days later, the Portuguese had to stave off the first Spanish invasion on their own, except that they had two British officers, charles O'Hara and the hon. John Crawford to help, advise and encourage them". In Journal of the Society for Army Historical Research, vol. 59, London, 1981, p. 25.
- "In April, because the war with Portugal was going badly for the Spanish troops, he [Count of Aranda] was ordered to return to Spain…" in María-Dolores, Albiac Blanco – El Conde de Aranda: los Laberintos del Poder, Caja de Ahorros de la Inmaculada de Aragón, 1998, p. 67.
- Alonso, José Ramon – Historia Política del Ejército Español, Editora Nacional, 1974, p. 49.
- The Gentleman's and London Magazine: Or Monthly Chronologer, 1741-1794, year of 1762, p. 483.
- " Count La Lippe, who was placed at the head of the allied forces, was one of the best soldiers of the age, and the Portuguese furnished a good raw material, although wretchedly equipped and officered. Nevertheless the heterogeneous body of English, Germans, and Portuguese collected under La Lippe made a very good fight of it, and Burgoyne, now a brigadier at the head of 3,000 cavalry, mostly Portuguese, distinguished himself...", in Cook, John D. and others – The Saturday Review of Politics, Literature, Science and Art, Vol. 41, John W. Parker and Son, 1876, p. 369.
- "... he was a man born to command, of eccentric character but highly educated, and one of the most renowned engineer officers: he soon established an order and discipline amongst the Portuguese troops, which gave them the ability to contend successfully with the Spaniards in this campaign, and which entitles him to distinction in all military annals. The Citadel of Elvas still perpetuates his name to Portuguese gratitude, Fort Lippe...", in Cust, Edward- Annals of the Wars of the Eighteen Century, Vol. III (1760-1783), London, 1858, p.74.
- "As Commander-in-Chief of the effete Portuguese army... he had repelled , in the brilliant peninsular campaigns of 1761-3, superior Franco-Spanish Forces." In Prothero, George Walter – The Quarterly Review, vol. 221, John Murray, 1914, p. 394.
- "The [Anglo-Portuguese] allies won by adroit marches and counter-marches, so that although…the enemy, by superior numbers, could possibly have won, they were always confronted by defenders in a good position and never dared to risk an all-out attack. A Campaign won without the major casualties of battle [for the Anglo-Portuguese]". In Journal of the Society for Army Historical research, vol. 59, London, 1981, p. 25.
- "... The movements of the Anglo-Portuguese troops forced the Spanish army of General Aranda to withdraw." In Mendes, J. Caria- John Hunter in Portugal, 1963, page 61 (originally published in Semana Médica, nr. 91, 22 January 1961 and translated by Dr. Guerra of the Wellcome Medical Library).
- Azevedo, J. Lúcio de – O Marquês de Pombal e a sua época, 2nd edition, Annuário do Brasil, Rio de Janeiro, p. 239.
- "In 1762 he was chosen to command the united English and Portuguese army in a victorious war against the Spanish". In Radant, Friedhelm – From Baroque to Storm and Stress, 1720-1775, Vol. IV of Literary History of Germany, Croom Helm, 1977, p. 137.
- Philippson, Martin – The Age of Frederick the great, vol. 15, Lea Brothers & Company, 1905, p. 103.
- "The Bourbons... planned the invasion in three divisions: the first, in the north of Portugal, between the Minho and the Douro; the second, in the middle, between the Douro and the Tagus; and the third, to the south of the Tagus, to co-operate on that side with the middle corps in its attempt upon Lisbon. The northern division... commenced hostilities; entered the Portuguese province of Trás-os-Montes and..." in Bisset, Robert – The History of the Reign of George III , Vol. I, Philadelphia, 1822, p. 188.
- "... this action disrupted the concentration of the third Spanish column that was to launch itself from Valencia into the Alemtejo, and therefore stalled the threat of a general engagement that Lippe so feared." In Speelman, Patrick and Danley, Mark – The Seven Year’s War: Global Views, 2012, p. 447.
- Journal of the Royal United Service Institution, Whitehall Yard, Vol. 63, W. Mitchell, United Kingdom, 1918, p. 196.
- "... In testimony to the cruel reality were the devastated fields, by order of the government, to embarrass the invasion by hunger, and along roadsides, the bones of the Spaniards slaughtered by the rural people..." In Azevedo, J. Lúcio de – O Marquês de Pombal e a sua época (in Portuguese), 2nd edition, Annuário do Brasil, Rio de Janeiro, p. 241.
- "the Spanish invaded Tralos Montes, and had to retreat with 'loss'…" in Neale, John Mason – A History of Portugal, Joseph Masters, London, 1846, p. 220.
- "[The initial victorious situation] began to change rapidly... In Madrid, the news that the Spanish troops had entered Oporto was expected; but the news that arrived was the complete opposite of this, and assumed a radical change in the conduct of military operations in Portugal. O'Reilly, who had reached to Vila Real and continued his advance [Towards Oporto], was checked …by 5,000 Portuguese, organized by British officers, whereby Sarriá ordered the 'general retreat' [back into Spain]… with the intention of returning to the original plan of reaching Lisbon through Almeida [in Province of Beira]." In López, Emilio González – Bajo las luces de la Ilustración: Galicia en los reinados de Carlos III y Carlos IV, Edic. Del Castro, 1977, page 22, ISBN 9788485134229.
- "Esquilache himself went to Portugal to reorganize Aranda’s logistical support." In Stein, Stanley and Stein, Barbara – Apogee of Empire: Spain and New Spain in the Age of Charles III, 1759-1789, Johns Hopkins University Press, 2004, chapter Imperilled Colonies and Spain’s Response.
- Sir Charles Grey to Shelburne, cited in Nelson, Paul David – Sir Charles Grey, First Earl Grey, Royal Soldier, family Patriarch, Associated University Presses, USA, 1996, p. 26.
- "Spanish successes in overrunning poorly defended Portuguese fortresses led to urgent Portuguese requests for British troops, and these helped to turn the side." Cambridge illustrated Atlas, Warfare: Renaissance to Revolution, 1492-1792, vol. II, 1996, p. 127.
- "Almeida, a key frontier town whose possession could open up the route to Lisbon, was in chaos. Its fortifications were second rate and its inhabitants terrified of Spanish aggression." In Speelman, Patrick and Danley, Mark – The Seven Year’s War: Global Views, 2012, p. 437.
- Francis, Alan David, Portugal 1715-1808, 1985, p. 150.
- "The garrison had... almost 3,000 men; but consisted of new recruits, and much of it deserted in the beginning of the siege, due to carelessness or connivance of the governor." In Lippe, Count of – Mémoire de la Campagne de Portugal de 1762, 1770, page 6.
- This huge desertion rate is abundantly corroborated by the testimony of several officers during the council of war of 25 August (the day of surrender); Manuel Rebelo de Sousa: "Given the great consternation in this fortress… and the fact that the garrison is small and of poor quality because of much desertion, I am in favor of surrender..." Or Domingos de Frias de São Payo: "The garrison [is] so tiny of infantry troops and auxiliary... because most of them left the garrison and defected...", in Costa, Fernando Dores – Nova História Militar de Portugal , Círculo de Leitores, Vol. II, Coordinator: António Hespanha, 2004, p. 339.
- "Two regular infantry and three militia regiments defended the place against 24,000 Spanish and 8,000 French...", in Speelman, Patrick and Danley, Mark – The Seven Year’s War: Global Views, 2012, p. 446.
- "Aranda…attacked Almeida, and after a siege of nine days, forced the garrison of fifteen hundred men to surrender." In Coxe, William – España Bajo el Reinado de la Casa de Borbon, Tome IV, Establecimiento Tipográfico, Madrid, 1847, p. 122.
- James, George – Lives of the most eminent foreign statesmen, vol. V, 1838, p.135.
- "Although this war was undertaken entirely in the national interests, nay, in defence of the very existence of Portugal, it was viewed with disfavour by an influential if not a large portion of the population…Colonel Anderson, belonging to the British contingent, and serving on the staff of the Count of Santiago, writes to Burgoyne: -'you may depend upon receiving the best of intelligence of the enemy’s motions; but hitherto the Conde de Santiago has found it very difficult to get good intelligence. It’s odd, you’ll say, when every peasant might reasonably be supposed to be a spy for him. These do not look on the Spaniards as their enemy; they think their cause the cause of the Jesuits and the cause of God. The people of condition, the Excellencies and the hidalgos have so insuperable a hatred to the minister, as to sacrifice their king, their country, and even their honour, to feed it. I have, however, the happiness here to be under as honest a man as ever lived [Portuguese commander Count of Santiago], with as good a heart as it is possible to imagine.'" In Edward Barrington de Fonblanque – Political and military episodes in the latter half of the nineteenth century, Macmillan and Co., London, 1876, pp. 36-37.
- Foy, Maximilien – History of the War in the Peninsula, Under Napoleon, vol. I, London, 1827, p. 255.
- In Azevedo, J. Lúcio de – O Marquês de Pombal e a sua época, 2nd edition, Annuário do Brasil, Rio de Janeiro, p. 241.
- Francis, Alan David, Portugal 1715-1808, 1985, p. 150.
- Godoy, Manuel – Memorias, Emilio La Parra López, Elisabel Larriba (editors), Publicaciones Universidad de Alicante, 2008, p. 756.
- "These peasants they [the Spaniards] hanged and shot whenever they fell into their hands; and their incensed comrades committed, in return, the most merciless barbarities on their prisoners". In Cassel, John; Smith, John and Howitt, William – John Cassel’s Illustrated History of England, vol. 5, London, 1861, p. 17.
- Academia Portuguesa da História- Anais, 1986, p. 401.
- "Outnumbered, he planned to attack where opportunities arouse and to harass the Spanish on the flanks and rear, while avoiding a general engagement against superior forces." In Speelman, Patrick and Danley, Mark – The Seven Year’s War: Global Views, 2012, p. 446.
- See Lippe, Mémoire de la Campagne de Portugal de 1762, 1770, pp. 25-28.
- Lippe – Mémoire de la Campagne de Portugal de 1762. 1770, pages 44-45.
- "... Portugal concentrated 15, 000 men [the complete Allied army consisted of 7,000 to 8,000 Portuguese plus 7,104 British] at the city of Abrantes and effectively barred the Spanish thrust. Then... the Spaniards` supply system failed, causing the troops to go hungry." In Santiago, Mark – The Red Captain: The Life of Hugo O'Conor, Commandant Inspector of the Interior Provinces of New Spain, Arizona historical Society, 1994, p. 14.
- "To Burgoyne, who had embarked for the Tagus with his light horse, early in May, and who now held the local rank of Brigadier-General, the organization of his brigade of 3,000 men, of whom nearly two-thirds were Portuguese, must, in spite of his love of soldiering, have been an irksome task, (...)", in Political and military episodes in the latter half of the nineteenth century, Macmillan and Co., London, 1876, p.35.
- "... mainly owing to the brilliant services of Brigadier-General Burgoyne, the Spaniards were defeated at Valencia de Alcántara and Vila Velha, and peace was made on 10th February 1763." In Encyclopædia Britannica: A-ZYM (William Smith, Day Kellogg, Thomas Baynes), vol. XIX, 1903, p. 550.
- "... Burgoyne’s successful leadership brought the Portuguese campaign to a victorious end by the time the Autumnal rains commenced in November 1762. The Seven Year’s War was virtually over." In Hargrove, Richard – General John Burgoyne, University of Delaware Press, 1983, p. 38.
- Jeudwine, John – Religion, commerce, liberty: a record of a time of storm and change, 1683-1793, Longmans, Green, 1925, p. 160.
- Letter from the Allied commander ( Earl of Loudoun) to the Earl of Egremont, Mação, 9 October 1762: "As soon as the enemy perceived our intention of drawing back, they pushed a corps over the river Alvito, to harass our rearguard, which was composed of the four English regiments, six companies of Portuguese grenadiers, a few of our light dragoons, and a regiment of Portuguese cavalry, with the four British field-pieces…but upon my ordering one of the guns to be brought up, which Major M. Bean conducted so effectually that hardly any shot was fired that did not take place among the enemy, they thought proper to retire…the country-people report, that they have buried 40 of the enemy. I can not omit mentioning to your Lordship that the Portuguese grenadiers showed upon this occasion, not only a very good countenance, but the utmost readiness and alertness in forming upon all the different occasions where it was necessary." In Boswell, James – The Scots Magazine, vol. XXIV, Edinburgh, 1762, p.551.
- "The attack was led by Lt. col. Charles Lee of the Dragoons of whom some, perhaps the majority, were Portuguese." In Francis, Alan David – Portugal 1715-1808, Tamesis Books Limited, London, 1985, p.158.
- "Abrantes: (...) In 1762, the Spaniards were defeated there by the Portuguese." In Encyclopédie du dix-neuvième siècle, vol I, Paris, 1858, page 106.
- Lippe – Mémoire de la Campagne de Portugal de 1762. 1770, pages 46- 47.
- Oman, Charles – A History of the Peninsular War, vol III, Clarendon Press, 1908, p.183, p.184 and p. 185.
- " Lippe had directed the Count St. João to drive the country during his retreat to the Lower Beira, and every thing that could not been carried off was destroyed: so that the enemy now found himself in a desert, without being able to procure either provisions, care, or peasants to assist them; the inhabitants had abandoned their villages, and carried off every thing (...)", in The Royal Military Chronicle, vol V, London, 1812, pp. 50-51.
- "... lower Beira could not provide for the enemy neither food, nor chariots nor peasants to build roads: the Count of Santiago had been ordered... to make disappear from this province everything that could be eaten or used as road; but what mainly contributed to the scarcity in the province was the cruel procedure of the enemy against the inhabitants, many of whom were killed, and their villages were looted and torched in revenge for the deaths caused by the peasants... thus, many inhabitants in order to escape the atrocities of the enemy, had left their homes, taking with them their cattle, food and whatever they could carry...", in Lippe, Count of – Mémoire de la Campagne de Portugal de 1762, 1770, pp. 39-41.
- "Lippe executed forty years before Lord Wellington, a similar manoeuvre to that in which the distinct English General took shelter behind the Lines of Torres Vedras, thereby opposing an invincible barrier to the army of Massena. Count of Aranda found himself in the same position as Marshal Prince d'Essling, or perhaps in an even more critical situation. In fact, as the Napoleon’s general, Aranda was forced to retreat or starve in Beira. (...) ", In Chagas, Pinheiro- História de Portugal, vol. VII, Lisboa, 1902, pp. 46-47.
- "The second zone [Lower Beira] is the one that leads most directly to the peninsula of Lisbon; but it is also the most difficult. Those travelling for the first time in the Beira railway line before reaching the Tagus, are impressed by the great picture of a cordillera rising steeply like a great wall (...). It is a formidable defensive position against which the two Spanish invasions of 1704 and 1762 were checked. During the first one, the Duke of Berwick quickly gave up forcing it. In the second, Count of Aranda managed to penetrate the mountains, but was quickly forced to retreat. What the Portuguese should want most is to see 'the Spaniards start the war through this province'. (...)" In Sardinha, António – A Questão Ibérica, Almeida, Miranda & Sousa, 1916, p. 274.
- "He [Lippe] succeeded in organizing the Portuguese troops and preparing means of defence so effectually that, when the Count d `Aranda arrived with the Spanish army upon the Tagus, he found, as was the case in our day, that the hilly country north of Lisbon was not to be forced even by a superior enemy." In Crowe Eyre Evans – The History of France, vol. IV, 1866, p. 286.
- A study on some of these defensive constructions can be found in Monteiro, Mário; Pereira, André – O Forte das Batarias Sobre a Ribeira do Alvito, AÇAFA On Line, nr. 1, 2008 Associação de Estudos do Alto Tejo.
- "... immobilized by supply shortages, unable to secure their lines of communication, and suffering disastrously high rates of desertion, the Bourbon armies withdrew, in early November, to bases across the Spanish border." In Anderson, Fred – Crucible of War: The Seven Years` War and the Fate of Empire in British North America, 1754-1766, USA, 2001, p. 497.
- Aspinall, Arthur – The Correspondence of George, Prince of Wales, 1770-1812, Oxford University Press, 1971, p. 12.
- Weller, Jac; Uffindell, Andrew – On Wellington: the Duke and his art of War, Greenhill Books, 1998, p.99.
- Mémoire de la Campagne de Portugal de 1762, 1770, Page 47.
- Mémoire de la Campagne de Portugal de 1762, 1770, page 48.
- Count of Lippe in his own words: "The Count Marshal, in order to embarrass the enemy... and to force its retreat back into Spain, risked ordering Townshend... to join the troops commanded by Lord Lenox... and after the junction…to take Penamacor in order to cut off the communication of the enemy army with... Ciudad Rodrigo ... [Spain] the arriving of this [combined] troops over the enemy’s right and its rearguard... Townshend…suddenly reappeared in [the Province of] Beira by a counter march of forty leagues through the most rude mountains of Portugal: (...) thanks both to Townshend’s skill and to the admirable perseverance of the Portuguese soldier... who left the traces of their bleeding feet in the sharp rocks...", in Lippe, Count of – Mémoire de la Campagne de Portugal de 1762. 1770, pages 41-43.
- "The alarm excited in the rear of the enemy by the troops under General Townshend, kept a considerable body of their troops engaged. On the 15th of Oct. the Count d' Aranda began to withdraw his advanced posts, and in a few days he retired with the whole army to his former position at Castello Branco." In The Royal Military Chronicle, vol V, London, 1812, p. 51.
- "Lippe… withdraws to Abrantes, which was strengthened to preclude the passage of the Aranda’s army [toward Lisbon], while at the same time, orders General Townshend... to cut off the retreat of the enemy army by occupying Penamacor and Monsanto... threatened with destruction as Count of Lippe moves its forces... Aranda retreats to Castelo Branco…the lower Beira is released, while Aranda, systematically harassed and threatened in the rear, eventually withdraws [back into Spain]". In Lousada, Abílio – Exército, jornal do (Army, journal of the), nr. 598 (August – September, 2010), Peres-Soctip Indústrias Gráficas SA, suplemento (chapter) "Schaumburg-Lippe e a Guerra Fantástica", p. 153. ISSN 0871-8598.
- "And Aranda... ingloriously withdrew his discouraged and diminished army...", in Ward, Sir Adolphus and others – The Cambridge Modern History, vol. 6, 1909, p. 369.
- "the Bourbon army began withdrawing back into Spain via Valencia, even though rearguard detachments harassed the advancing allied units." In Speelman, Patrick and Danley, Mark – The Seven Year’s War: Global Views, 2012, p. 452.
- Speelman, Patrick and Danley, Mark: "... the Spanish troops had retired to Spain as British detachments closely followed them to the frontier." In The Seven Year’s War: Global Views, 2012, p. 448
- "The frontier filled with Spanish deserters eager to be captured ...", in Speelman, Patrick and Danley, Mark – The Seven Year’s War: Global Views, 2012, p. 452.
- Speelman, Patrick and Danley, Mark: "Captain John Fenton of the Buffs led a detachment that overtook the Spanish rearguard... and seized control of the Portuguese border town of Salvaterra." In The Seven Year’s War: Global Views, 2012, p. 448.
- "The Spanish forcibly seized supplies from villages and torched those who offered resistance." In Speelman, Patrick and Danley, Mark – The Seven Year’s War: Global Views, 2012, p. 452.
- "In the campaign of 1704... the combined forces of France and Spain were palsied in the midst of their success by topographical obstacles and the want of provisions. In 1762, on the same ground, the same obstacles stopped the Spanish army under the orders of Count d'Aranda, and the auxiliary corps, commanded by the Prince de Beauvau, and compelled them to retreat before troops inferior both in quality and numbers." In Foy, Maximilien Sébastian – History of the War in the Peninsula, under Napoleon, Vol. II, London, 1827, p.21.
- See Arenas, Mar García – Los Proyectos del General Dumouriez Sobre la Invasión de Portugal in El Equilibrio de los Imperios: de Utrecht a Trafalgar, Actas de la VIII Reunión Científica de la Fundación Española de Historia Moderna (Madrid, 2-4 de Junio de 2004), vol. II, Fundación Española de Historia Moderna, 2005, p. 544.
- His report on Portugal earned Dumouriez the rank of colonel in the French army (1772), a reward of 18,000 francs (1768), the rank of Aide-Maréchal-Général of the French invading army sent to Corsica (1768) and he received the personal thanks of French foreign minister, Choiseul, in a public audience (1768). He was also rewarded with the rank of lieutenant-colonel of a Spanish corps (called the "foreign legion") by Charles III of Spain (which he rejected). Later, his military information about Portugal would be used by Junot ( first Napoleonic invasion of Portugal, 1807) and Soult (Second Napoleonic invasion of Portugal, 1809). See FEller, François-Xavier – Dictionnaire Historique, vol. VI, Paris, 1827, p. 169; see also Arenas, Mar García – Los Proyectos del General Dumouriez Sobre la Invasión de Portugal in El Equilibrio de los Imperios: de Utrecht a Trafalgar, Actas de la VIII Reunión Científica de la Fundación Española de Historia Moderna (Madrid, 2-4 de Junio de 2004), vol. II, Fundación Española de Historia Moderna, 2005, p. 550.
- Dumouriez, Charles – An Account of Portugal, as it Appeared in 1766 to Dumouriez, Lausanne (1775), and London (1797), chapter 5, pp. 134-135.
- Sales, Ernesto Augusto – O Conde de Lippe em Portugal, Vol 2, Publicações de Comissão de História Militar, Minerva, 1936, page 29.
- Letter of John Hamilton to Townsend, Alpedrinha, 24 October 1762, cited by Speelman, Patrick and Danley, Mark – The Seven Year’s War: Global Views, 2012, p. 448.
- Lippe, Mémoire de la Campagne de Portugal de 1762, 1770, Page 47 and page 48.
- Lippe, Mémoire de la Campagne de Portugal de 1762, 1770, p. 53
- Eduard Hay reporting to the Earl of Egremont. See British Scholar C. R. Boxer in Descriptive List of the State Papers Portugal, 1661-1780, in the Public Record Office, London: 1724-1765, Vol II, Lisbon, Academia das Ciências de Lisboa, with the collaboration of the British Academy and the P.R.O., 1979, p. 415. See also Costa, Fernando Dores – Nova História Militar de Portugal, Círculo de Leitores, Vol. II, Coordinator: António Hespanha, 2004, p. 358, footnote 280.
- Henry, Isabelle – Dumouriez: Général de la Révolution (1739-1823), L'Harmattan, Paris, 2002, p. 87.
- O'Callaghan, Edmund Bailey – Orderly Book of Lieut. Gen. Burgoyne, New York, 1860, Introduction, p. XVII.
- "Altogether, it was possible to collect an army of 40,000 men (p. 11)... With the army, by then reduced to 20,000 men… completely devoid of food, [Aranda] could do little (p.14)." In Ponce – La Casaca y la Toga: Luces y sombras de la reforma militar en el reinado de Carlos III Archived 2014-07-07 at Archive.is, Institut Menorquí d'Estudis, Mahón, 2011, Chapter 2: La campaña de Portugal en 1762, pp.11-21 Archived 2014-07-14 at the Wayback Machine..
- "… Spain ordered 40,000 men to march into Portugal (page 247) … The Spanish forces, when they arrived at the frontier, were reduced to 25,000 men, (...). This war, which might have crushed Portugal, gave it a degree of vigour and elasticity ... and produced a military spirit (page 254) ...", in Dumouriez, Charles – An Account of Portugal, as it Appeared in 1766 to Dumouriez, Lausanne (1775) and London (1797).
- General Dumouriez, Charles – An Account of Portugal, as it Appeared in 1766 to Dumouriez, Lausanne (1775), and London (1797), p. 247.
- See Dumouriez, Charles – An Account of Portugal, as it Appeared in 1766 to Dumouriez, Lausanne (1775), and London (1797), p.254.
- "... because the precedent disaster in the Fantastic War -as the invasion of 1762 is known in Portuguese historiography- should have been a lesson... Dumouriez's mission was to study the campaign of 1762, find the reasons of the failure; and through a detailed observation in situ of the geography and military state of the Portuguese crown, to devise an effective plan of campaign for a future war." In Arenas, Mar García. Los Proyectos del General Dumouriez Sobre la Invasión de Portugal In El Equilibrio de los Imperios: de Utrecht a Trafalgar, Actas de la VIII Reunión Científica de la Fundación Española de Historia Moderna (Madrid, 2-4 de Junio de 2004), vol. II, Fundación Española de Historia Moderna, 2005, p. 541.
- "The opinion of Dumouriez... was omitted in the copy that was to be delivered to the office of Charles III, by order of the French ambassador Ossun…since it could hurt Spanish susceptibility." See Arenas, Mar García – Los Proyectos del General Dumouriez Sobre la Invasión de Portugal in El Equilibrio de los Imperios: de Utrecht a Trafalgar, Actas de la VIII Reunión Científica de la Fundación Española de Historia Moderna (Madrid, 2-4 de Junio de 2004), volumen II, published in 2005, page 548 (see also p. 541).
- Here are the omitted references (disclosing that the Portuguese guerrillas were worsting the Spanish army): "The peasantry also form a militia…, who serve without pay, but engage with great fury, and are very formidable to the Spaniards, by their manner of fighting; as from the ignorance of their Generals, the neglect of their officers, and the want of discipline in the soldiers, the latter are ever exposed to ambuscades, assassinations, and sudden attacks." In An Account of Portugal, as it Appeared in 1766 to Dumouriez, Lausanne (1775), and London (1797), p.109 ; and also: García Arenas (2004), pp. 41, 73 and 74.
- "The Russian strategy 'was learned from British military leader Wellington, who, in alliance with Portuguese guerrilla forces' had resisted French invasion in the Peninsular War in a similar manner two years earlier." In Hough, Peter – Environmental Security, Routledge, New York, 2014, p. 58.
- "... his 'Grand Army' of French and allied troops was annihilated by the terrible winter, disease (typhus), and the stamina of the Russian guerrillas, using 'tactics similar' to those of Spain and Portugal." In Greer, Thomas; Lewis, Gavin – A Brief History of the Western World, 9th edition,Thomson wadsworth, 2004, p. 470.
- "For the next four months, the [French] army of Portugal maintained its vigil at a cost of more than twenty five thousand men. Of these, only two thousand were killed in action, and nearly eight thousand were captured or deserted, while the rest fell to disease and starvation." In Moon, Joshua – Wellington’s Two- Front War: The Peninsular Campaigns, at Home and Abroad, 1808-1814, University of Oklahoma Press, USA, 2012, p. 73.
- "... Wellington did not attempt to hold the Portuguese border. Instead, he ordered the entire countryside between the border and Lisbon to be laid waste and the inhabitants to take refuge in the mountains... Meanwhile, he had completed the construction of two formidable lines of fortification, the Lines of Torres Vedras, across the neck of the Lisbon peninsula… Masséna advanced deep into Portugal. At Bussaco he came upon the retreating Anglo-Portuguese army, attacked it, and was repulsed with heavy losses. Nevertheless, Wellington continued to retreat…and…slipped through the Lines of Torres Vedras, accompanied by most of the population of the Portuguese Province of Northern Estremadura…Masséna reached the Lines... For four months... the two armies remained in that position, facing each other without fighting. Yet whereas Lisbon was well supplied, the French were starving. Their marauding columns either found no food or were ambushed... Masséna ordered a retreat; one month later, his army reached its starting point, ciudad Rodrigo, reduced by one-third of its strength. Hunger, disease, and the guerrillas had taken at least twenty thousand French lives. As for the victors, their army had suffered no losses, but their victory had been won at the price of whole provinces destroyed and thousands of civilians starved, tortured, killed, or destitute. No phase of the Peninsular War was waged with more ferocity, and yet not a single major battle was fought." In Herold, J. Christopher – The Age of Napoleon, Mariner books, 2002, p. 226.
- Esdaile, Charles – The Peninsular War: a New History, Penguin Books, London, 2003, chapter 12.
- Cassel, John; Smith, John and Howitt, William – John Cassel’s Illustrated History of England, vol. 5, London, 1861, chapter I (Reign of George III), p. 20.
- See The Annual Register, Burke, Edmund, London, 1784 (General Index): " Castel Branco, defeat of the Spaniards in the Territory of,"
- "With the joy of victory, the fugitives [inhabitants] scattered over the fields were able to return home, and, after the withdrawal of the foreign army, the village of Castelo-Branco was hit by plague, and a lot of people died. (...)", cited in Academia Portuguesa da História- Anais, 1969, p. 132.
- Gipson, Lawrence – The British Empire before the American Revolution: the great war for the Empire: the culmination, 1760-1763, vol. 8, Knopf, 1954, p. 260.
- Prowse, D. W. – A History of Newfoundland: from the English, Colonial and Foreign Records, Heritage Books Inc., 2007, p. 311.
- Úrdañez, José Luis Gómez – Víctimas Ilustradas del Despotismo. El Conde de Superonda, Culpable y Reo, ante el Conde de Aranda, Universidad de la Rioja, 2009, p. 8 (part of the investigation project El Imperio Español, Desde la Decadencia a la España Discreta…, HAR 2009-13824).
- "... by mid 1762, [the allied commander, Lippe] had delivered the Lusitanian territory from the Spanish invaders, who kept only two borderland fortresses, and quickly celebrated the triumph of concluding such an honourable peace for Portugal, as the Peace of Hubertusburg was for Frederick the Great." In Medina, Eduardo de – Revista europea, Vol. 11, Madrid, 1878, p. 280.
- "In the opening of the campaign, success attended the arms of the invaders: they took Miranda, Braganza, and Almeida. Here their triumphs ceased. (...) Lippe arrived from Germany, and assumed the command. In his operations he was well assisted by General Burgoyne, and they had soon the glory of freeing the Portuguese soil from the Bourbon army." In Dunham, Samuel A. – "The History of Spain and Portugal", vol. 5, London, 1832, "pp.258-59".
- "... The Spaniards who had passed the mountains in three divisions [North, centre and South of Portugal] …after having taken many places, now imagined that they would soon become masters of the whole kingdom, found themselves under the necessity of abandoning their conquests, and of evacuating Portugal." In Beaumont, Alexander – "The History of Spain", London, 1809, p. 458
- "... The Portuguese, with the aid of their allies, had driven the Spaniards out of their country." In "Collections of the New York Historical Society: The John watts De Peyster publication fund series, vol. 7", The Society, 1875, p.213.
- Hart, Francis Russel – The Siege of Havana: 1762, Houghton Mifflin, 1931, p. 52.
- "Lippe deserves far more than the eight miniature gold cannon mounted on silver carriages [or six, according to other sources], 80,000 gold moidares, and numerous diamonds given to him by the Portuguese King upon his departure. So impressed was Oeiras that he retained Lippe’s services so he could reform the Portuguese army and modernize the kingdom’s defenses." In Speelman, Patrick and Danley, Mark – The Seven Year’s War: Global Views, 2012, p. 457.
- "The Spaniards proved far worse prepared than they had assured the French and lost Havana and Manila [13 August and 6 October, respectively] to British amphibious attacks in 1762. Charles III hoped that gains in Portugal would compensate him for losses elsewhere, regaining colonial losses in Portugal, but his army was not in a position to repeat Frederick II's successes in Silesia". In Black, Jeremy – America or Europe? British Foreign Policy, 1739-63, University of Exeter, UCL Press, 2002, pp. 26-27.
- "In September [this number increasing during the Bourbon retreat, in October], 3,000 French soldiers lay sick at Salamanca. (...)", in Danley Mark and Patrick Speelman – The Seven Year’s War: Global Views, Brill, 2012, p. 452.
- See Journal of the Society for Army Historical research, vol. 59, London, 1981, p.40.
- Stephens, Henry – The History of Portugal, G. P. Putnam's sons, 1891, p. 363.
- "In November the enemy attacked two small places, Marvão and Ouguela, but the long record of shameful capitulations at last ended. Ouguela was successfully held by a Portuguese commander, and Marvão... was defended by captain Brown of Armstrong’s with a British detachment and some Portuguese. He replied to the summons with a reminder of the recent fall of Havana and dispersed the assailants with a burst of shellfire." In Journal of the Society for Army Historical Research, vol. 59, London, 1981, p. 40.
- "A new wind swept the military [Portuguese] forces... Volunteers showed up to fight under his [Lippe’s] command, and the Portuguese forces increased both quantitatively and qualitatively ( page 129) ... In November... the [Franco-Spanish] allies had lost most of their infantry men and artillery, [while] Portuguese forces continued to grow up ( page 131)". In Daehnhardt, Rainer- Segredos da História Luso-Alemã, Publicações Quipu, Lisboa, 1998, ISBN 9728408072.
- "Our detachments pursued their rear-guard and took several prisoners. (...)", the allied commander Count of Lippe in Mémoire de la Campagne de Portugal de 1762. 1770, page 65.
- "This German officer [La Lippe], who had learned the war in the school of Frederick the Great of Prussia, repelled the invasion and forced the [Bourbon] allies to sign an armistice on the 1st December 1762. (...) ″, in Legrand, Théodoric – Histoire du Portugal (in French), Payot, 1928, p. 82.
- Tandeter, Enrique (coordinator): Germán Carrera Damas- Historia General de América Latina: processos americanos hacia la redefinición colonial (in Spanish), vol. 4, UNESCO, 2000, p. 22.
- "During its progression [through the Rio Negro valley, the Spanish] advancement was beyond San Carlos, since the Spaniards had managed to occupy the posts of Marabitanas and San Gabriel, from which they were dislodged by the Portuguese, who fortified them, under the German captain Felipe [Phillip Sturm]. They were armed with cannons brought by the Spanish commission of limits. (...)" In Ojer, Pablo- La Década Fundamental en la Controversia de Límites entre Venezuela y Colombia, 1881-1891 (in Spanish), Academia Nacional de la Historia, 1988, p. 292.
- " São Gabriel was founded during the Portuguese conquest in 1763, when a fort was built...", in United States Army Corps of Engineers- Report on Orinoco-Casiquiare-Negro Waterway. Venezuela-Colombia-Brazil, July 1943, Vol. I, 1943, p. 15.
- "The land on their own side [Portuguese side of the river Guaporé] afforded nothing on which they could rely, whereas the country of the [Spanish] Missions [left bank of the Guaporé] abounded with cattle... The Spaniards... designed... to intercept the communication [of the Portuguese in S. Rosa] with Para... and... Villa Bella. This blockade might be easily maintained, because they drew their supplies from the reductions; whereas the garrison [of S. Rosa], being confined to their own shore, would be distressed for food... and might thus be reduced without a blow. (...). The Portuguese…made an expedition against the Reduction of S. Miguel, which had been removed from the right Bank [to the left bank of the river Guaporé, in 1760, in accordance to the Treaty of Madrid, 1750]... they got possession of supplies which were intended for the [Spanish] army at Itanomas… the Portuguese kept possession of the territory of S. Miguel, which abounded with kine, horses and pigs... the Reduction of S. Martin voluntarily offered submission... D. António ventured to attack the Spaniards in their camp…the estacade was found too strong; but the boldness of this measure, thought unsuccessful, discouraged the Spaniards... they soon removed from their station... the encampment on the Mamoré was abandoned also: shortly after they fell back to S. Pedro: the Spaniards then returnrd to S. Cruz, and the expedition was broken up. The Portuguese then withdrew from the left shore." In Southern, Robert – History of Brazil, part third, London, 1819, p. 584.
- "... disease [caused by tropical conditions and the use of biological warfare by the Portuguese, according to the Spanish commander] and desertion had trimmed Verdugo [the Spanish Governor of Santa Cruz de la Sierra]’s levies from 610 to 303 by the time they reached San Pedro [head of the missions in Moxos, Bolivia, to where the Spanish remnants retreated]. (...) after two months on the Guaporé, the governor returned to Santa Cruz [Bolivia], leaving behind a skeleton force (...). In 1763 Moura retired from Mato Grosso the victor. He had advanced to the Guaporé [and beyond it, occupying Spanish territory in the left bank of this river until the end of the war: the territory of the Missions of S. Miguel and S. Martin, main sources of supply to the Spanish army.], fortified Portuguese positions on the river, and remained in the field as his rival retired. Moura’s service earned him a hero’s welcome from his commanders, a Knighthood, and eventually the office of Viceroy of Brazil." In Block, David – Mission Culture on the Upper Amazon: native Tradition, Jesuit enterprise and Secular Policy in Moxos, 1660-1880, University of Nebraska Press, 1994, p. 51.
- Marley, David- Wars of the Americas: a chronology of armed conflict in the New World, 1492 to the present, vol. II, ABC-CLIO, USA, 2008, p. 449 and p. 450
- Bento, Cláudio Moreira- Brasil, conflitos externos 1500-1945 (electronic version), Academia de História Militar Terrestre do Brasil, chapter 5: As guerras no Sul 1763-77.
- Ricardo Lesser- Las Orígenes de la Argentina, Editorial Biblos, 2003, see chapter El desastre”, see pp. 63-72.
- Bento, Cláudio Moreira- Rafael Pinto Bandeira in O Tuiuti, nr. 95, Academia de Historia Militar Terrestre do Brasil, 2013, pp. 3-18.
- Godoy, Manuel – Memorias, Emilio La Parra López, Elisabel Larriba (editors), Publicaciones Universidad de Alicante, 2008, pp. 781-782.
- "... What lessons can be drawn from the campaign? The effectiveness of the Portuguese forces was in large part due to Lippe’s basic plan bolstered by the nascent hatred and ineptitude of the Spanish invader. By remaining on the strategic defensive and occupying the important towns and passes that guarded the advance on Lisbon, the Allies were able to frustrate and upset Spanish advances time and again. It was his appreciation of the little war that mattered, not the war of big battalions. That he accomplished his task with such a rag task force is a testament to his capabilities as commander-in-chief. He understood how to use the scant Portuguese resources to their fullest. 'I think it very necessary frequently to engage the Portuguese', he wrote Lord Townshend, 'with the enemy by small detachments in order to use them to serious duty'. Thereby, he turned a liability into an asset" In Speelman, Patrick and Danley, Mark – The Seven Year’s War: Global Views, 2012, p. 457.
- "... the Portuguese were also quite good soldiers. Under the leadership of a renowned German warrior, the Count of Lippe-Schaumburg, they had already demonstrated... that they could be developed into a capital force. Moderate in their physical requirements [For example, during the Allied Peninsular campaign of 1813, which culminated with the expulsion of the Napoleon’s army from Spain, the average daily ration of a Portuguese soldier was –literally– half of the British soldier. See Henriques, Mendo C. – Vitória e Pirinéus, 1813: O Exército Português na Libertação de Espanha, Tribuna, Lisboa, 2008, p.35], inured to hardships, they were pre-eminently excellent on the march. Finally, the militia was very well adapted..." in The United Service, vol.132-139, American Periodical Series, 1850-1900, Lewis R. Hamersly & Company, 1904, p. 692.
- A few years after the 1762 invasion, during the Peninsular war (1808-1814), the prestige of the Portuguese soldier remained: "There are countless comments from British officers praising the bravery, steadfastness and skill of their Portuguese comrades [the Duke of Wellington used to call them the 'fighting roosters' of his Anglo-Portuguese army and asked Portuguese troops to reinforce his army in Belgian, during the campaign of Waterloo (they didn’t arrive in time)]. It is interesting to note that the French who fought against them agreed. General Hugo and his son new, from experience, that the Portuguese line was capable of withstanding the attacks of the best French regiments. Later on Baron Marbot, Marshal Massena’s ADC, concurred, adding that they had not been given proper credit for the part they played in the [Peninsular War]. (...)", in Chartrand, Rene – The Portuguese Army of the Napoleonic Wars, vol. 3, Osprey Publishing, New York, 2001, p. 41.
- Bradford in 1814, cited in Pivka, Otto Von – The Portuguese Army of the Napoleonic Wars, Osprey Publishing, New York, 1977, p. 19.
- "It was believed that Portugal, which had been thrown into the utmost disorder by a vicious court, would prove an easy conquest, and a united Spanish and French army at first met with little resistance; but the Portuguese people soon rose to defend their homes with such vigour, that all Choiseul’s hopes in that quarter were extinguished" In Wright, Thomas – The History of France, vol. II, London, 1858, p. 354.
- "Even after their decadence, the Portuguese had their moments: in the war of 1762, threatened by the forces of Spain and France, they resisted with glory and expelled the Spaniards out of their territory owing to well disciplined peasants." In Société d` Histoire Générale et d`Histoire Diplomatique – Revue d`Histoire Diplomatique, vol. 37, Éditions A. Pedone, Paris, 1969, p. 195.
- "... in 1762 Portugal was invaded by Franco-Spanish troops, which were checked by the resistance of rural populations." In Alegria, José A. and Palais des beaux-arts – Triomphe du Baroque, RTBF, Brussels, 1991, p.29.
- Guillon, Maxime – Port Mahon; La France a Minorque sous Louis XV (1766-1763) , E. Leroux, 1894, p. 107.
- Spanish Chief minister Ricardo Wall in a letter to Tanucci, 12 October 1762: "the circumstance of having to make war on a sterile country, and where each civilian is an enemy, makes it necessary to bring the supplies from Castile [Spain]... employing many troops to keep the conquered and to protect the [food] convoys...thus, the army possibly will not reach Lisbon before the Winter... contrary to what was planned [this prediction would prove prophetic since three days later the Franco-Spanish army initiated its disastrous retreat]". In Alarcia, Diego T. – El ministerio Wall: la "España discreta" del "ministro olvidado", 2012, p. 155.
- Monglave, Eugène – Histoire de l'Espagne, Chez Raymond Éditeur, Paris, 1825, p. 271.
- "Preparations the Spanish Government made for war after signing the compact with France focused more on Portugal than the colonies. (...)", In Greentree, David – A Far-Flung Gamble – Havana 1762, Osprey Publishing, Oxford, 2010, p. 30.
- Feelings of humiliation and shame caused by the Spanish defeat against Portugal and Great Britain were especially intense: "The ′shameful Treaty of Paris of 1763′, so Floridablanca, [former Spanish prime minister] called to a Treaty that... had highlighted the weakness of Spain as a leading power." In Albistur, Rafael Olachea – Estudios sobre el siglo XVIII (in Spanish), edited by Vicente Palacio Atard, Instituto Jeronimo Zurita C.S.I.C., Madrid, Anexos de la revista Hispania, nº 9, 1978 , p. 201. In another example, Larrey wrote in Madrid, 28 November 1763, to count Bernstorff : "the outcome of an unfortunate war, that didn’t provide other benefit to Spain than the knowledge of her weakness, the shame of disclosing it to the whole Europe, and the certainty that she is not capable of fighting successfully even against Portugal." In Albistur, Rafael – Estudios sobre el siglo XVIII, 1978 , p. 201.
- Dumouriez, Charles – An Account of Portugal, as it Appeared in 1766 to Dumouriez, Lausanne (1775), and London (1797), p. 247.
- Reflexiones Histórico-Militares que manifiestan los Motivos Porque se Mantiene Portugal Reino Independiente de España y Generalmente Desgraciadas Nuestras Empresas y que Lo Serán Mientras No se Tomen Otras Disposiciones , Borzas, 28 November 1772; cited in In José Tertón Ponce – La Casaca y la Toga: Luces y sombras de la reforma militar en el reinado de Carlos III Archived 2014-07-07 at Archive.is, Institut Menorquí d'Estudis, Mahón, 2011, La campaña de Portugal en 1762, pp.11-21, p.21.
- Cited in In José Tertón Ponce – La Casaca y la Toga: Luces y sombras de la reforma militar en el reinado de Carlos III Archived 2014-07-07 at Archive.is, Institut Menorquí d'Estudis, Mahón, 2011, Chapter 2: La campaña de Portugal en 1762, pp.11-21 Archived 2014-07-14 at the Wayback Machine., p.21.
- Cornide, José (published by Juan M. Rosario Cebrián) – Los Viajes de José Cornide por España y Portugal de 1754 a 1801, Real Academia de la Historia, Madrid, 2009, pp. 847-848.
- "But this Spanish navy, beaten everywhere, allows the British conquest of the Antilles, part of the Philippines and even Belle Isle-en-Mer. On land, defeat in Portugal (...). (...) the fateful pact did nothing but aggravate the situation, already so disastrous." In Lauvriére, Émile – Histoire de Louisiane Française : 1673-1939, G.-P. Maisonneuve, 1940, p. 395.
- "Spain’s Charles III, following the military episode with Portugal, was increasingly reluctant to risk repeating his misfortunes of 1762-63... he wanted to have peace until the end of his reign..." In Brecher, Frank W.- Securing American Independence: John Jay and the French Alliance , Praeger Publishers, USA, 2003, pp. 50-51.
- "All this neglect regarding the militia did not avoid, however, a profound reform of the army, during the government of the third Charles. Especially after the first crashes of the reign, during the Spanish participation in the Seven years' War: the loss of Havana and the disastrous expedition against Portugal in 1762. (...)", In Ponce, José Luis Terrón – Ejército y Política en La España de Carlos III Archived 2014-07-07 at Archive.is, vol. 37, de Collectión Adalid, Ministerio de Defensa, Secretaria General Técnica, 1997, p. 23 or page 5 of chapter La Monarquia Militar, part I: El Hecho Militar Durante El Reinado De Carlos III, La Situación del Ejército Y Su Reforma (in the electronic edition).
- "... for it was from the trauma and humiliation suffered in the conflict that the third of its Bourbon kings, Charles III, and his ministers derived the sense of purpose and direction required for the formulation and implementation of the all – embracing process of modernization which historians refer to as the 'Bourbon reforms' ". In Fisher, John Robert – Bourbon Peru, 1750-1824, Liverpool University Press, UK, 2003, p. 28.
- Carnota, John Smith A. – The Marquis of Pombal, 2nd edition, Longmans, Green, Reader, and Dyer, London, 1871, p.182.
- Abbot Béliardi, the agent of Choiseul at Madrid, writing on 18 October 1762: "(...) news of the taking of Havana has gravely upset the Spanish nation... there is no consolation for the irreparable loss of one third of Spain’s naval forces, surrendered without a cannon shot." In Stein, Stanley and Stein, Barbara – Apogee of Empire: Spain and New Spain in the Age of Charles III, 1759-1789, Johns Hopkins University Press, 2004, chapter "Imperiled Colonies and Spain’s Response".
- Úrdañez, José Luis Gómez – Víctimas Ilustradas del Despotismo. El Conde de Superunda, Culpable y Reo, ante el Conde de Aranda , Universidad de la Rioja, 2009, pp. 14-15 (part of the investigation project El Imperio Español, Desde la Decadencia a la España Discreta..., HAR 2009-13824).
- Galdós, Benito – Guerra de la Independencia, vol I, Algaba Ediciones, Madrid, 2008, pp. 427-428.
- 700 regular infantry troops, 200 dragoons, 1,800 militiamen and 1200 Indians. See Marley, David- Wars of the Americas: a chronology of armed conflict in the New World, 1492 to the present, vol. II, ABC-CLIO, USA, 2008, p. 441.
- "The 400 Portuguese infantry men, 40 troopers, 32 gunners, 230 militiamen … are reinforced from Rio de Janeiro by a 10-ship convoy … although conveying only 65 soldiers… ", in Marley, David- Wars of the Americas: a chronology of armed conflict in the New World, 1492 to the present, vol. II, ABC-CLIO, USA, 2008, p. 441-442.
- " [Portuguese colonel] Osório built a small fort which he called Santa Teresa, where he took shelter with 400 men and little artillery (January 1763). Next April, Ceballos, who had gathered in Maldonado a well provisioned army of more than 3,000 men with much artillery, invested the Lusitanian position. After a weak resistance, Osório surrendered with the remaining 130 men. All the other had deserted." In Instituto Histórico e Geográfico do Rio Grande do Sul- Revista do Instituto Histórico e Geográfico do Rio Grande do Sul, Edições 132-134, Brazil, 1998, p. 12.
- "…Osório , arrives at Castilhos on the shores of Merín Lagoon with 400 men of the Dragoon Regiment of rio Pardo, 10 small artillery pieces, plus a work column, to commence construction … of a border keep to be called Fort Santa Tereza…", In Marley, David- Wars of the Americas: a chronology of armed conflict in the New World, 1492 to the present, vol. II, ABC-CLIO, USA, 2008, p. 441.
- "Four days later, the small fort of San Miguel fell into the hands of Cevallos, abandoned by the garrison of 30 men which stayed there under cap. João Teixeira.", In Instituto Histórico e Geográfico do Rio Grande do Sul- Revista do Instituto Histórico e Geográfico do Rio Grande do Sul, Edições 132-134, Brazil, 1998, p. 12.
- "In the whole region of the Rio Grande, the Portuguese government did not have more than 1,000 soldiers, including regular and militia troops, spread over several trims." In Instituto Histórico e Geográfico do Rio Grande do Sul- Revista do Instituto Histórico e Geográfico do Rio Grande do Sul, Edições 132-134, Brazil, 1998, p. 12.
- "(…). In this 'race for the Rio Grande [territory]', the border of Rio Pardo was the only one who resisted the Spanish invasion, thanks to Barreto Pereira Pinto courage and, above all, Francisco Pinto Bandeira, which shattered the army of captain Antonio Cattani on January 1, 1763. Pinto Bandeira, with only 230 dragoons and adventurers of St. Paul, fell like a hurricane over the 2,500 enemy soldiers. 'Never saw this territory such a stampede.' (…). Cattani’s troops disbanded in panic. The commander, no time to put on the uniform, fled in underwear." In Barbosa, Fidélis D.- História do Rio Grande do Sul, Edições Est, 4th edition, Porto Alegre, 1976, p. 60.
- "While the Spanish army advanced along the coast, fully reaching their goals, another enemy column, consisting of five hundred militiamen from the Corrientes Province and about 2,000 Guaranis came from the Misiones Orientales against Rio Pardo, under lieutenant colonel Antonio Cattani and fortified next to the stream of Santa Barbara…" in Vellinho, Moysés- Fronteira, Editora Globo, 1975, p. 105.
- Branco, José- Obras do Barão do Rio Branco, vol. VI, Ministério das Relações exteriores, Brazil, p.3.
- Flores, Moacyr- Dicionário de história do Brasil, Edipucrs, 2004, p. 80. ISBN 9788574302096
- Arenas, Mar García. Los Proyectos del General Dumouriez Sobre la Invasión de Portugal in El Equilibrio de los Imperios: de Utrecht a Trafalgar, Actas de la VIII Reunión Científica de la Fundación Española de Historia Moderna (Madrid, 2-4 de Junio de 2004), vol. II, Fundación Española de Historia Moderna, published in 2005, pp. 537–550.
- Bento, Cláudio Moreira- Rafael Pinto Bandeira in O Tuiuti, Nº 95, Academia de Historia Militar Terrestre do Brasil, 2013.
- Francis, Alan David. The Campaign in Portugal, 1762 in Journal of the Society of Army Historical Research, Vol. 59, nr. 237 (pp. 25–43). Society of Army Historical Research. London, 1981.
- Úrdañez, José Luis Gómez. Víctimas Ilustradas del Despotismo. El Conde de Superunda, Culpable y Reo, ante el Conde de Aranda. , Universidad de la Rioja, 2009, (part of the investigation project El Imperio Español, Desde la Decadencia a la España Discreta…, HAR 2009-13824)
- Barrento, António. Guerra Fantástica, 1762: Portugal, o Conde de Lippe e a Guerra dos Sete Anos. Lisboa, Tribuna, 2006.
- Bento, Cláudio Moreira- Brasil, conflitos externos 1500-1945 (electronic version), Academia de História Militar Terrestre do Brasil, chapter 5: As guerras no Sul 1763-77.
- Chagas, Manuel Pinheiro. História de Portugal, vol. VII, Lisboa, 1902
- Costa, Fernando Dores (Coordinator: António Hespanha). Nova História Militar de Portugal, vol. II, Círculo de Leitores, 2004. ISBN 9789724230719
- Coxe, William. España Bajo el Reinado de la Casa de Borbon, Tome IV, Establecimiento Tipográfico, Madrid, 1847.
- Daehnhardt, Rainer. Segredos da História Luso-Alemã. Lisboa, Publicações Quipu, 1998. ISBN 9728408072.
- Dellon, Gabriel (and other authors) – Portugal nos Séculos Dezassete e Dezoito: Quatro Testemunhos, Lisóptima Edições, 1989, ISBN 9789729394027
- Dumouriez, Charles. An Account of Portugal, as it Appeared in 1766 to Dumouriez, Lausanne (1775), and London (1797).
- Francis, Alan David. Portugal 1715-1808, Tamesis Books Limited, London, 1985.
- Gipson, Lawrence. The British Empire before the American Revolution: the great war for the Empire: the culmination, 1760-1763, Vol VIII. Knopf, 1954.
- Hull, Anthony H. Charles III and the revival of Spain. University Press of America, 1980. ISBN 978-0-8191-1022-0
- Lesser, Ricardo- Las Orígenes de la Argentina, Editorial Biblos, 2003, chapter "El desastre” ( pp. 63-72).
- Madariaga, Salvador de. The fall of the Spanish American empire. Greenwood Press, 1975. ISBN 978-0-8371-8267-4
- Marley, David- Wars of the Americas: a chronology of armed conflict in the New World, 1492 to the present, vol. II, ABC-CLIO, USA, 2008.
- Mourinho, António. Invasão de Trás-os-Montes e das Beiras na Guerra dos Sete Anos Pelos Exércitos Bourbónicos, em 1762, através da Correspondência Oficial ..., Series II, Vol 31, Anais da Academia Portuguesa de História, Lisboa, 1986.
- Ortiz, Altagracia. Eighteenth Century Reforms in the Caribbean, Fairleigh Dickinson Univ Press, 1983, ISBN 9780838630082
- Petrie, Sir Charles. King Charles III of Spain. Constable, 1971. ISBN 0094572704
- Ponce, José Tertón - La Casaca y la Toga: Luces y sombras de la reforma militar en el reinado de Carlos III. Institut Menorquí d'Estudis, Mahón, 2011, La campaña de Portugal en 1762, pp.11-21.
- Sales, Ernesto Augusto. O Conde de Lippe em Portugal, Vol 2. Publicações de Comissão de História Militar, Minerva, 1936.
- Savelle, Max; Fisher, Margaret Anne. The origins of American diplomacy: the international history of Angloamerica, 1492-1763. Macmillan, 1967.
- Schaumburg-Lippe, William. Mémoire de la Campagne de Portugal de 1762. 1770.
- Simms, Brendan. Three Victories and a Defeat: The Rise and Fall of the First British Empire. Penguin Books (2008)
- Speelman, Patrick and Mark, Danley. The Seven Year’s War: Global Views. Brill, 2012, chapter 16: Strategic illusions and the Iberian War of 1762 (pp. 429–460). ISBN 978-90-04-23644-8.
- Stein, Stanley and Stein, Barbara – Apogee of Empire: Spain and New Spain in the Age of Charles III, 1759-1789, Johns Hopkins University Press, 2004. ISBN 9780801881565
- The Royal Military Chronicle, vol V, London, 1812.