|Michael I Cerularius|
|Ecumenical Patriarch of Constantinople|
The enthronement of Michael I Cerularius, from the Madrid Skylitzes
|See||Ecumenical Patriarchate of Constantinople|
|Term ended||21 January 1059|
|Predecessor||Alexius I Studites|
|Successor||Constantine III Lichoudas|
|Birth name||Michael Keroularios|
Constantinople, Byzantine Empire
|Died||21 January 1059|
Constantinople, Byzantine Empire
Michael I Cerularius or Keroularios ( Greek: Μιχαήλ Α΄ Κηρουλάριος; c. 1000 – 21 January 1059 AD) was the Ecumenical Patriarch of Constantinople from 1043 to 1059 AD. He is most notable for his role in the events that led to the Great Schism in 1054. 
Michael Cerularius was born in Constantinople around 1000 AD, being ordained into the Church from a young age. He is noted for disputing with Pope Leo IX over church practices in respect of which the Roman Church differed from Constantinople, especially the use of unleavened bread in the Eucharist.  Notable disagreements were also exchanged over other theological and cultural issues, ranging from the issue of papal supremacy in the Church to the filioque clause and other disagreements between the Patriarchates.
- "The first pope who used it [the Donation] in an official act and relied upon it, was Leo IX; in a letter of 1054 to Michael Cærularius, Patriarch of Constantinople, he cites the "Donatio" to show that the Holy See possessed both an earthly and a heavenly imperium, the royal priesthood."
Some scholars say that this letter of September 1053, the text of which is available in Migne, Patrologia Latina, vol. 143, coll. 744-769, was never actually despatched, but was set aside, and that the papal reply actually sent was the softer but still harsh letter Scripta tuae of January 1054. 
Leo IX assured the Patriarch that the donation was completely genuine, not a fable or old wives' tale,[ citation needed] arguing that only the apostolic successor to Peter possessed primacy in the Church.
This letter of Pope Leo IX was addressed both to Michael Cerularius, Patriarch of Constantinople, and Leo of Ohrid, Archbishop of Bulgaria, and was in response to a letter sent by Leo, Metropolitan of Achrida to John, Bishop of Trani (in Apulia), that categorically attacked the customs of the Latin Church that differed from those of the Greeks. Especially criticized were the Roman traditions of fasting on the Saturday Sabbath and consecration of unleavened bread. Leo IX in his letter accused Constantinople of historically being the source of heresy and claimed in emphatic terms the primacy of the Bishop of Rome over even the Patriarch of Constantinople, who would have none of it. It can be argued that in 1054, the Patriarch's letter to Pope Leo IX initiated the events which followed, because it claimed the title "ecumenical patriarch" and addressed Pope Leo as "brother" rather than "father."
Pope Leo IX sent an official delegation on a legatine mission to treat with the Patriarch. Members of the papal delegation were: cardinal Humbert of Silva Candida, papal secretary Frederick of Lorraine, who was Cardinal-Deacon of Santa Maria in Domnica, and Peter, Archbishop of Amalfi. Soon upon their arrival in Constantinople, news were received that pope Leo IX had died on 19 April. Since official position and authority of papal legates was dependent upon the pope who authorized them to represent him, the news of Leo's death placed his envoys in an awkward position.  In spite of that, they decided to proceed with their mission, but even before any religious discussions were held, problems arose regarding some basic formalities and ceremonies. During the initial audience, Patriarch refused to meet with papal envoys in their official capacity and left them waiting with no further audience for months.
During that time, from April to July 1054, cardinal Humbert and his colleagues continued with their activities in Constantinople, taking part in informal religious discussions on various issues. Their behavior was seen as inappropriate by the Patriarch. Despite the fact that their legatine authority officially ceased after popes death, cardinal Humbert and his colleagues decided to engage in open confrontation with the Patriarch. On Saturday, 16 July 1054, they produced a Charter of Excommunication (lat. charta excommunicationis),  directed against Patriarch Michael of Constantinople, Archbishop Leo of Ohrid, and all of their followers. On the same day, cardinal Humbert and his colleagues entered the church of the Hagia Sophia during the divine liturgy and placed the Charter on the altar. 
Soon after that, Patriarch decided to react. On 20 July 1054, a synod of 21 metropolitans and bishops was held in Constantinople, presided by Cerularius. The council decided to excommunicate cardinal Humbert and his colleagues.   Only the three men were anathematized, and a general reference was made to all who support them, but there was no explicit excommunication of the entire Western Christianity, or the Church of Rome. On Sunday 24 July the conciliar anathema was officially proclaimed in the Hagia Sophia Church.
The events of 1054 caused the Great Schism and led to the end of the alliance between the Emperor and the Papacy, and caused later Popes to ally with the Normans against the Empire. Patriarch Michael closed the Latin churches in his area, which exacerbated the schism. In 1965, those excommunications were rescinded by Pope Paul VI and Patriarch Athenagoras, when they met in the Second Vatican Council. Although the excommunication delivered by Cardinal Humbert was invalid, this gesture represented a significant step towards restoring communion between Rome and Constantinople.
The short reign of the Empress Theodora saw Michael intrigue against the throne. Michael Psellus notes that while their initial relations had been cordial, once Theodora took the Imperial throne, they entered into open conflict, as Michael "was vexed because the Roman Empire was being governed by a woman", and on this topic "he spoke his mind freely.".  The historian suggests that Theodora would have deposed Michael for his open effrontery and sedition, had she lived longer.
Cerularius had a hand in negotiating the abdication of Michael VI Stratiotikos, convincing him to step down on 31 August 1057, in favour of the rebellious general Isaac, for whom the army declared on 8 June.  The emperor duly followed the patriarch's advice and became a monk. Having had a role in bringing him to the throne, Cerularius next quarrelled with Isaac I Komnenos over confiscation of church property. Michael went so far as to take the highly symbolic step of donning the purple shoes ceremonially reserved for the Emperor. Michael apparently planned a rebellion, to overthrow the Emperor and claim the Imperial Throne for himself or for his relative Constantine Doukas. Isaac exiled Michael to Proconnesus in 1058 and, as Michael refused to step down, had Psellus drew up the Accusation of heresy and treason against him.  Cerularius died before coming to trial.
- Charanis 1969, p. 209-212.
- Michael Cærularius - Catholic Encyclopedia article
- Migne's Patrologia Latina, Vol. 143 (cxliii), Col. 744-769. Also Mansi, Sacrorum Conciliorum Nova Amplissima Collectio, Vol. 19 (xix) Col. 635-656.
- Charanis 1969, p. 209-210.
- Charanis 1969, p. 210.
- Mansi 1774, p. 676-679.
- Mansi 1774, p. 811-822.
- Charanis 1969, p. 211.
- Psellus, p. 269.
- Norwich, pg. 332
- Psellus, p. 315. Editor's n. I. See also Skylitzes, p. 464, note 56.
- Charanis, Peter (1969) . "The Byzantine Empire in the Eleventh Century". A History of the Crusades. 1 (2nd ed.). Madison: University of Wisconsin Press. pp. 177–219.
- Migne's Patrologia Latina, Vol. 143 (cxliii), Leo IX Epistolae Et Decreta .pdf - 1.9 Mb. See Col. 744B-769D (pgs. 76-89) for Leo IX's letter.
- Mansi, Joannes Dominicus, ed. (1774). Sacrorum conciliorum nova et amplissima collectio. 19. Venetia: Antonius Zatta.
- Michael Psellus, Fourteen Byzantine Rulers (The Chronographia), E.R.A. Sewter, trans. New York: Penguin, 1966.
- Siecienski, Anthony Edward (2010). The Filioque: History of a Doctrinal Controversy. Oxford University Press.
- Skylitzes, John (John Wortley, trans. and J-C. Cheynet, notes). Cambridge: University Press, 2010.
|Eastern Orthodox Church titles|
Patriarch of Constantinople
Constantine III Leichoudes