The Battle of Pavia by unknown Flemish artist (16th century)
|Commanders and leaders|
Part of a series on the
|History of Italy|
The Italian Wars, often referred to as the Great Wars of Italy and sometimes as the Habsburg–Valois Wars, were a series of Renaissance conflicts from 1494 to 1559 that involved most of the Italian states as well as France, the Holy Roman Empire, Spain, England and the Ottoman Empire.
An Italic League that ensured peace in the peninsula for 50 years had collapsed in 1492 with the death of Lorenzo De Medici, key figure of the bloc and ruler of Florence. In 1494, Charles VIII of France invaded the Italian Peninsula and occupied the Kingdom of Naples on the ground of a dynastic claim. However, he was forced to leave the occupied territories after a northern Italian alliance won a tactical victory against him at the Battle of Fornovo. In an attempt to avoid the mistakes of his predecessor, Louis XII annexed the Duchy of Milan in the north of Italy and signed an agreement with Ferdinand of Aragon (already ruler of the two biggest Mediterranean islands, Sicily and Sardinia) to share the Kingdom of Naples. Nevertheless, Ferdinand of Aragon turned on Louis XII and expelled French forces from the South after the battles of Cerignola and Garigliano.
After a series of alliances and betrayals, the Papacy decided to side against French control of Milan and supported Charles V, Holy Roman Emperor and heir of Aragon territories in Italy. Following the battles of Bicocca and Pavia, France lost its control of Milan to the Habsburgs. However, mutinous German Protestant troops of Charles V sacked Rome in 1527: this event was a turning point in the development of the European Wars of Religion and caused Charles V to focus on the growth of Protestantism in the Holy Roman Empire.
King Henry II of France took advantage of the situation and tried to establish supremacy in Italy by invading Corsica and Tuscany. However, his conquest of Corsica was reversed by the Genoese admiral Andrea Doria and his troops in Tuscany were defeated at the Battle of Scannagallo by the Florentines and the Imperials. With the abdication of Charles V, Philip II of Spain inherited the Italian possessions. The last significant confrontation, the Battle of St Quentin (1557), was won by Emmanuel Philibert of Savoy for the Spanish and international forces: this led the restoration of the French-occupied Piedmont (predecessor state of Italy) to the House of Savoy.
In 1559, the Treaty of Cateau-Cambresis was signed. The political map of Italy was largely affected by the end of the wars: Naples, Sicily and Milan had been confirmed to remain under Spanish control; the House of Savoy settled in Turin and made Italian its official language; Florence absorbed Siena into a Tuscan state; and the Papacy initiated the counter-reformation with the Council of Trent. In a jousting tournament held to celebrate the peace treaty, Henry II of France was killed by a lance: the instability that followed his death led to the French Wars of Religion.
- 1 Prelude
- 2.1 First Italian War of 1494–1498 or King Charles VIII's War
- 2.2 Second Italian War or King Louis XII's War (1499–1504)
- 2.3 War of the League of Cambrai (1508–1516)
- 2.4 Italian War of 1521–1526
- 2.5 War of the League of Cognac (1526–1530)
- 2.6 Italian War of 1536–1538
- 2.7 Italian War of 1542–1546
- 2.8 Italian War of 1551–1559
- 3 Aftermath and impact
- 4 Arms and armies
- 5 Historiography
- 6 Citations
- 7 Bibliography
- 8 Further reading
Following the Wars in Lombardy between Venice and Milan, which ended in 1454, Northern Italy had been largely at peace during the reigns of Cosimo de' Medici and Lorenzo de' Medici in Florence, with the notable exception of the War of Ferrara in 1482–1484.
Charles VIII of France improved relations with other European rulers in the run up to the First Italian War by negotiating a series of treaties: in 1493, France negotiated the Treaty of Senlis with the Holy Roman Empire; on 19 January 1493, France and the Crown of Aragon signed the Treaty of Barcelona; and later in 1493, France and England signed the Treaty of Étaples.  
Ludovico Sforza of Milan, seeking an ally against the Republic of Venice, encouraged Charles VIII of France to invade Italy, using the Angevin claim to the throne of Naples as a pretext. When Ferdinand I of Naples died in 1494, Charles VIII invaded the peninsula with a French Army  of twenty-five thousand men (including 8,000 Swiss mercenaries), possibly hoping to use Naples as a base for a crusade against the Ottoman Turks.  For several months, French forces moved through Italy virtually unopposed, since the condottieri armies of the Italian city-states were unable to resist them. Charles VIII made triumphant entries into Pisa on November 8, 1494, Florence on November 17, 1494,  and Rome on December 31, 1494.  Upon reaching the city of Monte San Giovanni in the Kingdom of Naples, Charles VIII sent envoys to the town and the castle located there to seek a surrender of the Neapolitan garrison. The garrison killed and mutilated the envoys and sent the bodies back to the French lines. This enraged the French army so that they reduced the castle in the town with blistering artillery fire on February 9, 1495 and stormed the fort, killing everyone inside.  This event was then called the sack of Naples. News of the French Army's sack of Naples provoked a reaction among the city-states of Northern Italy and the League of Venice was formed on March 31, 1495.
The League was specifically formed to resist French aggression. The League was established on 31 March after negotiations by Venice, Milan, Spain and the Holy Roman Empire.  Later on the League consisted of the Holy Roman Empire, the Duchy of Milan, Spain, the Papal States, the Republic of Florence, the Duchy of Mantua and the Republic of Venice. This coalition, effectively, cut Charles' army off from returning to France. After establishing a pro-French government in Naples, Charles started to march north on his return to France. However, in the small town of Fornovo he met the League army.
The Battle of Fornovo was fought on July 6, 1495, after an hour the League's army was forced back across the Taro river while the French continued marching to Asti, leaving their carriages and provisions behind.  Francesco Guicciardini wrote that both parties strove to present themselves as the victors in that battle, but the eventual consensus was for a French victory, because the French repelled their enemies across the river and succeeded in moving forward, which was their reason for fighting in the first place.  In contemporary tradition, though, the battle counted as a Holy League victory, because the French forces had to leave and lost their provisions. To the Italian coalition, however, it was at best a pyrrhic victory, in that its strategic outcome and long-term consequences were unfavorable. Although the League managed to force Charles VIII off the battlefield, it suffered much higher casualties  and could not prevent the opposing army crossing the Italian lands as it returned to France.
As a result of Charles VIII's expedition, the regional states of Italy were shown once and for all to be both rich and comparatively weak, which sowed the seeds of the wars to come. In fact, the individual Italian states could not field armies comparable to those of the great feudal monarchies of Europe in numbers and equipment.
Meanwhile, in the Kingdom of Naples, after initial reverses, such as the disastrous defeat by the French at the Battle of Seminara on June 21, 1495, Ferdinand II, King of Naples, with the able assistance of the Spanish general Gonzalo Fernández de Córdoba,  eventually reduced the French garrison in the Kingdom of Naples. Thus, Charles VIII lost all that he conquered in Italy. King Charles VIII died on April 7, 1498, and was succeeded to the throne of France by his cousin, Louis II, Duke of Orléans, who became Louis XII of France. 
Ludovico Sforza retained his throne in Milan until 1499, when Charles's successor, Louis XII of France, invaded Lombardy  and seized Milan on September 17, 1499.  Louis XII justified his claim to the Duchy of Milan by right of his paternal grandfather, Louis duc d'Orléans having married Valentina Visconti in 1387. Valentina Visconti was the heir to the Duchy of Milan in the Visconti dynasty. The marriage contract between Valentina Visconti and Louis, duc d'Orléans, guaranteed that in failure of male heirs, she would inherit the Visconti dominions. However, when the Visconti dynasty died out in 1447, the Milanese ignored the Orleans claim to the Duchy of Milan and re-established Milan as a republic. However, bitter factionalism arose under the new republic which set the stage for Francesco Sforza (father of Ludovico Sforza) to seize control of Milan in 1450. 
Louis XII was not the only foreign monarch with dynastic ambitions in the Italian Peninsula. In 1496, while Charles VIII was living in France trying to rebuild his army, Maximilian I of the Holy Roman Empire invaded Italy, to resolve the ongoing war between Florence and Pisa, called the "Pisan War".  Pisa had been at war almost continually since the early 14th century. In 1406 after a long siege, Pisa fell under the control of the Florentine Republic.  When King Charles VIII of France, invaded Italy in 1494, the Pisans rose up against the Florentines and ousted them from Pisa and established Pisa as an independent republic again.  When the King Charles VIII and the French Army withdrew from Italy in 1495, the Pisans were not left to fight the Florentines alone. Much of northern Italy was suspicious of the rising power of Florence. Already during 1495, Pisa had received arms and money from the Republic of Genoa. Additionally, the republic of Venice and Milan supported Pisa by sending them cavalry and infantry troops. 
This was part of the ongoing conflict between Pisa and Florence that Emperor Maximilian vowed to resolve in 1496. Just as Ludovico Sforza had invited Charles VIII into Italy in 1494, now in 1496, he invited Maximilian I of the Holy Roman Empire into Italy to resolve the conflict between Pisa and Florence.  In the conflict between the Florentines and the Pisans, Sforza had favored the Pisans. In the eyes of Maximilian I and the Holy Roman Empire, the Pisan War was causing distractions and divisions within the members of the League of Venice. This was weakening the anti-French League and Maximilian sought to strengthen the unity of League by settling this war. The worst thing that Maximilian feared was more French involvement in Italian affairs. However, Ludovico Sforza invited Maximilian I and the Holy Roman Empire into Italy in order to strengthen his own position.  When the Florentines heard about Maximilian's intention of coming to Italy to "settle" Florence's war with Pisa, they were suspicious that the "settlement" would be heavily inclined toward Pisa. Thus, the Florentines rejected any attempted settlement of the war by the Emperor until Pisa was back under Florentine control. 
The Florentines knew that another option was open to them. They knew that the French, under their new king—Louis XII—were intent on returning to Italy. Florence chose to take their chances with the French rather than the Holy Roman Empire. They felt that France might help them re-conquer Pisa. 
Louis XII was in fact intending to invade Italy to establish his claim over the Duchy of Milan. Louis was also entertaining an ambition to stake a claim to the Kingdom of Naples. This claim was even weaker than Louis XII's claim to Milan. The claim to the Kingdom of Naples was really King Charles VIII's claim. However, Louis demanded recognition of the claim solely because he, Louis, was the successor to Charles VIII.  However, Louis was aware of the hostility that was developing among his neighbors, in regards to French ambitions in Italy. Consequently, Louis XII needed to neutralize some of this hostility. Accordingly, in August 1498, Louis XII signed a treaty with Archduke Philip, son of Maximilian I, Emperor of the Holy Roman Empire which secured the borders between the Holy Roman Empire and France.  In July 1498, Louis renewed the Treaty of Étaples of 1492 with Henry VII of England. In August 1498, the Treaty of Marcoussis was signed between Louis XII and Ferdinand and Isabel. This Treaty resolved none of the outstanding territorial disputes between Spain and France, but agreed that both Spain and France "have all enemies in common except the Pope." 
In July 1499, the French Army left Lyon in France and invaded Italy with 27,000 men (10,000 of which were cavalry and 5,000 of which were Swiss mercenaries). Louis XII placed Gian Giacomo Trivulzio in command of his army. In August 1499, the French Army came across Rocca di Arazzo the first of series of fortified towns in the western part of the Duchy of Milan.  Once the French artillery batteries were in place, it took only five hours to open a breach in the walls of the town. After conquering the town, Louis ordered that the garrison and part of the civil population be executed in an attempt to instill fear in his enemies, crush their morale and encourage the quick surrender of the other Strongholds in western Milan.  The strategy was a success and the campaign for the duchy of Milan ended swiftly. On September 5, 1499, terms were negotiated for the surrender of the city of Milan and on October 6, 1499, Louis made his triumphant entry into Milan. 
Once Louis XII was installed in Milan, he came under real pressure from the Florentines to assist them in re-conquering Pisa. King Louis and his advisors were annoyed at what they considered to be an arrogant request by the Florentines, since in their recent struggle to conquer Milan, the Florentines had maintained strict neutrality despite their long record of pro-French diplomacy.  However, Louis was mindful that if he were to conquer Naples, he must cross Florentine territory on the road to Naples. Louis XII needed good relations with Florence. So finally, on June 29, 1500, a combined French and Florentine army laid siege to Pisa. Within a day French guns had knocked down 100 feet of the city walls Pisa. An assault was made at the breach, but the French were surprised by the strong resistance thrown up by the Pisans. The French Army was forced to break off the siege on July 11, 1500, and retreat to the north. 
As part of Louis XII's continuing attempt to pacify or neutralize his neighbors to prevent them from obstructing his ambitions in Italy, Louis XII opened discussions with King Ferdinand and Queen Isabella of Spain. On November 11, 1500, Louis signed the Treaty of Grenada.  The Treaty of Grenada memorialized Louis XII's agreement with Ferdinand II of Aragon, King of Spain, to divide the Kingdom of Naples between themselves. Then Louis set off marching south from Milan towards Naples. King Louis XII's agreement with Spain was heavily criticized by contemporaries—including Niccolò Machiavelli in his masterpiece The Prince. Modern historians also criticize the Treaty of Grenada by calling it "foolish" on Louis XII's part. They allege, as does Machiavelli, that Louis XII did not need to invite Spain into Italy. Louis XII had achieved everything he needed in the Treaty of Marcoussis, that he had signed two years earlier (see above). The Treaty of Grenada did nothing but bind Louis XII's own hands. Once involved in Italian affairs, Spain would work to the detriment of France in Italy. Indeed, this is just what happened.
By 1500, a combined French and Spanish force had seized control of the Kingdom of Naples.  Louis XII appointed Louis d'Armagnac, Duke of Nemours as viceroy at Naples. On October 12, 1501,  the new viceroy took over administration of Naples. However, the new French viceroy proved to be more concerned with extending the French share of the kingdom than he was in ensuring that the Spanish received their share. This did much to aggravate relations between France and Spain.  These disagreements about the terms of the partition led to a war between Louis and Ferdinand. By 1503 Louis, having been defeated at the Battle of Cerignola on April 28, 1503,  and Battle of Garigliano on December 29, 1503,  was forced to withdraw from Naples, which was left under the control of a Spanish viceroy, General Gonzalo Fernández de Córdoba.
Pope Julius II became pope upon the death of Pope Pius III on 18 October 1503.  He was extremely concerned about the territorial expansion of the Republic of Venice in northern Italy. Pope Julius was not alone in his fear of Venetian territorial ambitions. Being from Genoa, Pope Julius knew of the Genoese hatred of Venice for forcing the other states out of the rich Po Valley as the Republic expanded its frontiers across northern Italy.  Additionally, Emperor Maximilian was upset with the Venetian seizure of Duchy of Friuli and the bordering County of Gorizia, which Maximilan claimed as his rightful inheritance.  Furthermore, King Louis XII of France had been firmly established in Milan since 1500. Louis XII now saw Venice as a threat to his position in Milan. Moreover, King Ferdinand of Naples (and of Aragon) resented the fact that Venice held a number of towns in southern Italy along the Adriatic coast.
The circumstances were set for Pope Julius to form the League of Cambrai on December 10, 1508, in which France,  the Papacy, Spain, the Duchy of Ferrara and the Holy Roman Empire agreed to restrain the Venetians.  Although the League destroyed much of the Venetian army at the Battle of Agnadello on May 14, 1509,  it failed to capture Padua. 
By 1510, relations between Louis XII and the pope had broken down. Accordingly, the Pope changed sides in the war and allied itself with Venice, which was now less of a threat to the pope due to previous Venetian defeats. In March 1510, Pope Julius brokered a deal with the Swiss Cantons that brought 6,000 more Swiss troops into the war against the French. Following a year of fighting over the Romagna, during which the Veneto-Papal alliance was repeatedly defeated, the Pope proclaimed a Holy League against the French in October 1511.  This league rapidly grew to include England, Spain, and the Holy Roman Empire.
French forces under Gaston de Foix inflicted an overwhelming defeat on a Spanish army at the Battle of Ravenna on April 11, 1512.  Foix was killed and the French were forced to withdraw from Italy when the Swiss invaded and conquered Milan.  The Swiss reinstated Massimiliano Sforza to the ducal throne of Milan.  However, the victorious Holy League fell apart over the subject of dividing the spoils, and in March 1513 Venice allied with France, agreeing to partition Lombardy between them. 
Louis mounted another invasion of Milan but was defeated at the Battle of Novara on June 6, 1513. The Battle of Novara would be the last in which the traditional Swiss tactic of charging in three columns would be used with success.  The victory of the Holy League at Novara was quickly followed by a series of Holy League victories against the Venetians at La Motta on October 7, 1513, the French at Guinegate on August 16, 1513, and the Scots at Flodden Field on September 9, 1513.
Overshadowing all, however, was the death of Pope Julius II on February 20, 1513,  which left the League without effective leadership. On January 1, 1515, Louis XII also died  and was succeeded to the throne of France by his nephew, Francis I. Francis I continued Louis XII's war against the League of Cambrai in Italy by leading a French and Venetian Army against the Swiss and routing them at Marignano on September 13–14, 1515.  This victory decisively broke the string of victories that the Swiss had enjoyed against the Venetians and the French. Following the Battle of Marignano, the League of Cambrai or Holy League collapsed as both Spain and the new pope, Leo X, gave up on the notion of placing Massiliano Sforza on the ducal throne of Milan.  By the treaties of Noyon on August 13, 1516, and Brussels, the entirety of northern Italy was surrendered to France and Venice.
After three years of relative peace, the elevation of Charles of Spain to Holy Roman Emperor on June 28, 1519, led to a collapse of relations between France and the Habsburgs. Francis I himself had been a candidate for election as Holy Roman Emperor before Charles V was chosen. This led to a personal rivalry between Francis I and Charles V that was to become one of the fundamental conflicts of the sixteenth century.  Francis' candidacy for Emperor had been supported by Pope Leo X. Thus, Pope Leo now had a real fear of Charles V. Charles' empire included the Kingdom of Naples, the northern border of which was just forty miles from the Vatican.
The deterioration of relations between the Habsburgs and Francis I provided Francis I with a pretext for war with Charles. However, just when Francis I began to count on the support of Pope Leo in a war against Charles V, Pope Leo suddenly made peace with the Emperor and sided with the Holy Roman Empire against France. Soon Francis I was surrounded by enemies. Not only was Charles V emperor, but he also remained King of Spain. Thus Francis I faced war from the east (the Holy Roman Empire) and the west (Spain). Then to make matters worse, Henry VIII of England joined the pope (Pope Leo X died in 1522 and was replaced by Adrian VI who died in 1523 and was succeeded by Clement VII) and the emperor in their war on France.
Charles V took Milan from the French in 1521 and returned it to Francesco Sforza, the Duke of Milan, in 1522.  The French were outmatched by the Spanish arquebusier tactics and suffered crippling defeats at Bicocca on April 27, 1522,  and Sesia, against Spanish troops under Fernando de Avalos, on April 30, 1524. With Milan in Imperial hands, Francis personally led a French army into Lombardy in 1525, only to be utterly defeated and captured at the Battle of Pavia on February 24, 1525.  With Francis imprisoned in Spain, a series of diplomatic maneuvers centered around his release ensued, including a special French mission sent by Francis' mother Louise of Savoy to the court of Suleiman the Magnificent that would result in an Ottoman ultimatum to Charles – an unprecedented alliance between Christian and Muslim monarchs that would cause a scandal in the Christian world. Suleiman used the opportunity to invade Hungary in the summer of 1526, defeating Charles' allies at the Battle of Mohács on August 29, 1526. Despite all these efforts, Francis was required to sign the Treaty of Madrid in January 1526,  in which he surrendered his claims to Italy, Flanders, and Burgundy in order to be released from prison.
In 1526, Pope Clement VII, alarmed at the growing power of the Empire, formed the League of Cognac against Charles V on May 22, 1526.  Members of the League were the Papal States under Pope Clement VII, France under King Francis I,  England under Henry VIII, the Republic of Venice, Republic of Florence, and the Duchy of Milan.
The League planned a war against the Empire to begin in early 1526. The Imperial troops in Italy were extremely discontented because they were owed so much back pay that was not forthcoming. In some places in Italy, the Imperial troops were even refusing to take the field of battle until they were paid.  The military commanders of the League of Cognac wished to take advantage of this disorder and demoralization of the Imperial troops and to attack the troops in early 1526.  However, the League commanders knew that they were soon to be joined by some Swiss mercenaries they had hired. So they delayed the start of the attack until they were joined by the Swiss.
Meanwhile, Venetian troops under the Duke of Urbino were marching westward across northern Italy to join their allies, the Papal troops. Along the way, they discovered that a revolt had occurred in Lodi, a town under the rule of the Visconti family. A disaffected Italian infantry captain from Lodi was willing to open the gates of the town to the Venetian Army. Consequently, the Venetians were able to quickly occupy Lodi on June 24, 1526. 
Another revolt broke out in the city of Milan against the rule of Francesco Sforza II, Duke of Milan. Milan had been bouncing back and forth between control by the Sforza family and control by the Kingdom of France since 1499, when Ludovico Sforza was driven out of Milan by French King Louis XII. Except for two months in early 1500, Milan had remained under the control of the French for twelve years. In 1512, however, political control of Milan shifted back to the Sforza family—under Massimiliano Sforza—for three years until King Francis I of France was able to drive out the Sforzas once more. Milan was again under French rule for another six years before Francesco Sforza kicked the French out in November 1521. Francis I returned to Milan and restored French control in the city in October 1524 only to lose it again in February 1525 in the Treaty of Madrid, which had been forced on him by Emperor Charles V. One of Francis's first goals in joining the League of Cognac was to repudiate the Treaty of Madrid and regain control over Milan. However, French troops had not yet entered into the new war in Italy and their agreement to do so remained secret.
The uprising in Milan in the summer of 1526 was coordinated with the defenders of the "Castello" in Milan. The populace was upset over the behavior of the troops in the garrison of the Castello while they were on leave in town. 
In June 1526, Hugo of Moncada, the commander of Imperial forces in Italy, was sent as an ambassador from the Emperor to Pope Clement VII in the Vatican.  His message from the Emperor was that if the Papal States aligned themselves with the French in the current war, the Holy Roman Empire would seek to use both the Italian towns of Colonna and Siena against the papacy. Pope Clement VII recognized the threat these two cities presented to the Papal States should they join forces with the Imperial troops already in Italy. Accordingly, the pope withdrew his forces at just the time the French forces entered Lombardy in northern Italy. 
Suddenly the League started to fall apart. Venice had suffered devastating damage in the Italian Wars. Its subject lands—the "Terraferma"—had been ravaged from 1509 to 1516. At one time or another during the Italian Wars, every city in Venice's Terraferma, except for the city of Treviso, had been lost to an enemy.  As a result, Venice refused to contribute any more troops to the war effort. After 1529, Venice would cease all direct involvement in the Italian Wars.  Realizing that their goal of reconquering Milan was no longer on the table, the French army left Lombardy and headed back to France. With the withdrawal of French forces from Lombardy, Charles V proceeded to subdue Florence, and, in 1527, Rome itself was sacked by mutinous Imperial forces. Clement was imprisoned by Imperial troops  and offered no further resistance to Charles V. With the conclusion of the Treaty of Cambrai in 1529, which formally removed Francis from the war, the League collapsed; Venice made peace with Charles V, while Florence was placed again under the Medici.
When the Treaty of Cambrai was being signed in August 1529,  thus ending the War of the League of Cognac, Emperor Charles V was already making his way to Italy.  This trip to Italy and the settlement of Italian affairs during the trip is traditionally viewed as marking the end of Italian political liberty and independence and the beginning of a long period of control  by the Spanish and the Holy Roman Empire. Charles V's influence and control of affairs in Italy had grown out of King Louis XII's much criticized invitation to Spain under the Treaty of Grenada (1500) to join in settling problems in Italy. (See § Second Italian War above.) In 1500, Spain had been a separate and independent kingdom under King Ferdinand and Queen Isabella. Now under Charles V, both Spain and the Holy Roman Empire were part of the same political entity. Even in 1500, the influence that Spain could bring to Italian politics was significant, but it was still minor compared to the power that Charles V could now exercise in Italy. The main goal of that power and influence was now aimed at France, the very power that had invited the Spanish into Italy in the first place.
Thus, this third war between Charles V and King Francis I of France  began with the death of Francesco Maria Sforza, the duke of Milan during the night of November 1–2, 1535.  Upon his death, Francesco Sforza left no heirs. Emperor Charles V was on another trip to Italy when he heard about the death of Sforza.  When the representatives of Emperor Charles V took charge of the Duchy of Milan upon the death of Sforza, there were no protests or uprisings among the people of Milan.  Nor were there any objections from any other Italian states. There were, however, objections from France. Francis I, king of France, firmly believed that Asti, Genoa and the Duchy of Milan were all rightfully his.  Thus recovering Milan for France remained the primary goal for Francis I. So when Charles bequeathed the Duchy of Milan to his son Philip, King Francis I of France invaded Italy. At about this time, Francis told his council that he had allowed Emperor Charles V to become too strong in Italy. This was an open admission by a French King that Louis XII's signing of the Treaty of Grenada in November 1500 had been a mistake.
In late March 1536, a French army under the command of Philippe de Chabot, seigneur de Brion advanced into Piedmont with 24,000 infantry and 3,000 horse.  The French Army captured and entered Turin in early April 1536, but failed to take Milan. Meanwhile, the pro-French section of the population in the city of Asti rose up against and overthrew their Imperial occupiers. 
In response to the capture of Turin by the French, Charles V invaded Provence, advancing to Aix-en-Provence. Charles took Aix on August 13, 1536, but could go no further because the French Army blocked all roads leading to Marseilles.  Consequently, Charles withdrew back to Spain rather than attacking the heavily fortified town of Avignon.
Charles V's fruitless expedition to Provence distracted his attention from events in Italy. French troops operating in the Piedmont were joined by 10,000 Italian infantry and a few hundred horses on a march to Genoa.  These Italian troops had been raised by Guido Rangoni, Galeotto Pico della Mirandola and other members of the military nobility of southern Lombardy. Galeotto had gained control of Mirandola in 1533 by killing his uncle Giovanni Francesco Pico della Mirandola.  In preparation for his invasion of Italy, Francis I's ambassador to the Ottoman Empire, Jean de La Forêt, obtained, in early 1536, a treaty of alliance between the Ottoman Empire and France. By the end of 1536 an Ottoman fleet was poised off the coast of Genoa ready to strike in coordination with the land forces marching toward Genoa. However, when the land forces arrived before Genoa in August 1536, they found that the garrison at Genoa had recently been reinforced.  Furthermore, an expected uprising among Fregoso partisans in Genoa did not materialize. So the land forces moved by Genoa and marched on into the Piedmont where they captured and occupied Carignano along with three other towns between Turin and Saluzzo: Pinerolo, Chieri and Carmagnola. The active participation of the Ottomans in the war was not significant, but their very entry into the war had a curbing effect on the actions of Charles V. Fighting a two front war, against the Ottomans in the east and the French in the west, did not appeal to Charles V. Consequently, by 1538, Charles was ready for peace.
Francis I, King of France, allied himself once more with Suleiman I of the Ottoman Empire and on July 12, 1542, declared war on the Holy Roman Empire.  Francis I launched his final invasion of Italy against the town of Perpignan. A Franco-Ottoman fleet under the command of Ottoman admiral Hayreddin Barbarossa captured the city of Nice on August 22, 1543,  and laid siege to the citadel. The defenders of the citadel were relieved within a month. For Christian and Islamic troops to act in coordination to attack a Christian town was regarded as shocking. Thus, in this attack on Nice, King Francis needed to play down the role of the Ottoman Turks.  However, Francis I did something even more scandalous when he turned the French naval port of Toulon over to Barbarossa to use as winter quarters for the Ottoman fleet. 
Once again Milan was the pretext for the War of 1542–1546.  The French Army commanded by François de Bourbon, Count d'Enghien defeated an Imperial army at the Battle of Ceresole on April 14, 1544.  However the French failed to penetrate further into Lombardy.
On January 6, 1537, Alessandro de Medici, the Duke of Florence, was assassinated by his distant cousin, Lorenzino de' Medici.  Alessandro had the support of the Holy Roman Empire as he was married to Charles V's daughter, Margaret. With the Duke of Florence removed, some citizens of Florence attempted to establish a republic in the city, while other pro-Medici citizens sought to install the seventeen-year-old Cosimo de' Medici as the new Duke. The republican faction raised an army under the command of Piero Strozzi.  The pro-Medici faction sought assistance from Charles V to defeat the republican faction. King Francis I supported the now-exiled republican faction as a means of preventing Charles V from taking over Florence.  On June 4, 1544, the army of republican exiles from Florence under the command of Piero Strozzi was defeated by an Imperial army under the command of Philippe de Lannoy and Ferrante da Sanseverino, Principe di Salerno.
Charles V and Henry VIII of England then proceeded to invade northern France, seizing Boulogne and Soissons.  At one point the English and Imperial troops were within sixty miles of Paris.  A lack of cooperation between the Spanish and English armies, coupled with increasingly aggressive Ottoman attacks, led Charles to abandon these conquests, restoring the status quo once again.
On March 31, 1547, King Francis I died and was succeeded by his son, Henry II of France.  In 1551, Henry II declared war against Charles with the intent of recapturing Italy and ensuring French, rather than Habsburg, domination of European affairs. An early French offensive against Lorraine was successful, but the attempted French invasion of Tuscany was stopped in 1553. The French were decisively defeated at the Battle of Marciano on August 2, 1554. Nonetheless, as a result of this war, France obtained three French-speaking cities: Metz, Toul and Verdun. 
In 1556, during the course of the war, Charles V abdicated the Imperial throne as well as the throne of Spain. He abdicated the Imperial throne of the Holy Roman Empire to his brother, who became Ferdinand I of the Holy Roman Empire. The throne of Spain went to Charles' son, who became Philip II of Spain. Thus, the abdication of Charles V split the Habsburg empire that had surrounded France. From this point on, Spain and the Holy Roman Empire would no longer act in absolute coordination as they had under the personal union of Charles V. Gradually, the two Habsburg entities would drift off separately in their own directions following their own divergent interests.
At this point the focus of the war shifted away from Italy and toward Flanders, where Philip, in conjunction with Emmanuel Philibert of Savoy, decisively defeated the French at St. Quentin on August 10, 1557.  Following the defeat at St. Quentin, the French did recover and took some new initiatives in the war. England's entry into the war in 1557 led to the French capture of Calais in January 1558.  Additionally, French armies plundered Spanish positions in the Low Countries. Nonetheless, Henry II was forced to accept the Peace of Cateau-Cambrésis, which was signed on April 3, 1559. In that treaty, Henry II renounced any further claims to Italy. 
In France, Henry II was fatally wounded on 10 July 1559, in a joust held during the celebrations of the peace. His death led to the accession of his 15-year-old son Francis II, who in turn died on 5 December 1560. The French monarchy was thrown into turmoil, which increased further with the outbreak of the French Wars of Religion in 1562. The states of Italy were reduced to second-rate powers, and Milan and Naples came under the rule of the Spanish Habsburgs.
The Italian Wars had a number of consequences for the work and workplace of Leonardo da Vinci. He had planned a large horse statue, " Gran Cavallo", in 1495, but the seventy tons of bronze intended for the statue were instead cast into weapons to save Milan. Later, following a chance encounter with Francis I after the Battle of Marignano, Leonardo agreed to move to France and bring along his masterpiece Mona Lisa, which has remained in France to this day. Leonardo spent his final years in France in a house provided by Francis I.
Additionally, the Italian Wars represented a revolution in military technology and tactics—some historians consider these wars the dividing point between modern and medieval times.  Contemporaneous historian Francesco Guicciardini wrote of the initial 1494 French invasion:
Now owing to this invasion of the French everything was turned upside down in a sudden storm…sudden and violent wars broke out, ending with the conquest of a state in less time than it used to take to occupy a villa. The siege and taking of a city became extremely rapid and achieved not in month but in days and hours. 
Infantry underwent profound developments during the Italian Wars, evolving from a primarily pike- and halberd-wielding force to a more flexible arrangement of arquebusiers, pikemen, and other troops. While landsknechts and Swiss mercenaries continued to dominate during the early part of the wars, the Italian War of 1521 demonstrated the power of massed firearms in pike and shot formations.
A 1503 skirmish between French and Spanish forces first demonstrated the utility of arquebuses in battle. The Spanish general, Gonzalo de Codoba, faked a retreat, luring a contingent of French men-at-arms between two groups of his arquebusiers. As the French army stepped between the marksmen, volleys of bullets battered them on both flanks. Before the French could attack the vulnerable arquebusiers, a Spanish cavalry charge broke the French forces and forced their retreat. While the French army escaped, the Spanish inflicted severe casualties. 
So successful was the employment of firearms in the Italian Wars that Niccolò Machiavelli, often characterized as an enemy of the use of the arquebus, wrote in his treatise on The Art of War that all citizens in a city should know how to fire a gun. 
Heavy cavalry—the final evolution of the fully armored medieval knight—remained major players on the battlefields of the Italian Wars. Here, the French gendarmes were generally successful against heavy mounted troops from other states, owing significantly to their excellent horses, but on the contrary they turned out to be very vulnerable to the pikermen. The Spanish besides using heavy cavalry also used light cavalry called Jinetes for skirmishing.
Artillery, particularly field artillery, become an indispensable part of any first-rate army during the Italian Wars. During his invasion of Italy, Charles VIII employed the first truly mobile siege train: culverins and bombards mounted on wheeled carriages, which could be deployed against an enemy stronghold immediately after arrival. The French siege arsenal brought with it multiple technological innovations. Charles' army pulled cannons with horses rather than the oxen typically used at the time.  Additionally, French cannons, made using methods used to cast bronze church bells, achieved a lightness and mobility previously unheard of.  Perhaps the most important improvement the French made to cannons, however, was the creation of the iron cannonball. Before the Italian Wars, artillery fired stone balls that often shattered on impact.  The invention of the water mill allowed furnaces to generate enough heat to melt iron to be smelted into cannonballs.  With this technology, Charles’ army could level, in a matter of hours, castles that had formerly resisted sieges for months and years. 
The armies of the Italian Wars were commanded by a wide variety of leaders, from mercenaries and condottieri to nobles and kings.
Much of the fighting during the Italian Wars took place during sieges. Successive invasions forced Italy to adopt increasing levels of fortification, using such new developments as detached bastions that could withstand sustained artillery fire.
The Italian Wars are one of the first major conflicts for which extensive contemporary accounts from people involved in the wars are available, owing largely to the presence of literate, and often extremely-well educated, commanders. The invention of modern printing, still less than one century old, undoubtedly played a large role in the memorialization of the conflict as well.
The naming of the component conflicts within the Italian Wars has never been standardized and varies among historians of the period. Some wars may be split or combined differently, causing ordinal numbering systems to be inconsistent among different sources. The wars may be referred to by their dates or by the monarchs fighting them.
A major contemporary account for the early portion of the Italian Wars is Francesco Guicciardini's Storia d'Italia (History of Italy), written during the conflict and advantaged by the access that Guicciardini had to papal affairs.
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|Wikimedia Commons has media related to Italian Wars.|
- Le Gall, Jean-Marie, Les guerres d'Italie (1494-1559): une lecture religieuse. Geneva: Droz, 2017.
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