Michael I Cerularius (c. 1000-1059), also known as Michael Keroularios or Patriarch Michael I, was the Patriarch of Constantinople from 1043 to 1059.

Biography

Born in Constantinople, Patriarch Michael I Cerularius is noted for disputing with Pope Leo IX over church practices where the Roman Church differed from Constantinople, especially the use of unleavened bread in the Eucharist.

Pope Leo IX sent a letter to the Patriarch in 1054, that cited a large portion of the Donation of Constantine believing it genuine. See the 1913 Catholic Encyclopedia, Volume 5, entry on Donation of Constantine,

Leo IX assured the Patriarch that the donation was completely genuine, not a fable or old wives tale, so only the apostolic successor to Peter possessed that primacy and was the rightful head of all the Church. Little did Leo IX know that he cited and testified to the authenticity of the most stupendous fraud in European history.

This letter of Pope Leo IX was addressed both to Michael Cærularius, Patriarch of Constantinople, and Leo, Metropolitan of Achrida, and was in response to a letter sent by Leo, Metropolitan of Achrida to John, Bishop of Tranum (Bulgaria), 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.


In 1054, it can be argued that 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 Cardinal Humbert of Silva Candida on a legatine mission to treat with the Patriarch. Cerularius refused to meet with Cardinal Humbert and kept him waiting with no audience for months.

Thus, Cardinal Humbert of Silva Candida delivered a notice of excommunication against Patriarch Michael on July 16, 1054, despite the death of Pope Leo three months prior and thus the invalidity of the excommunication. [Many accounts refer to this as a bull of excommunication but it is not a bull unless it is signed by a pope and Pope Leo had not seen it or signed it.] Michael in turn excommunicated the cardinal and the Pope and subsequently removed the pope's name from the diptychs starting the East-West Schism.

This schism 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, of course, 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.

Michael also quarrelled with Emperor Isaac I Komnenos who he himself had put on the throne as a puppet (Michael went so far as to wear wore the purple shoes ceremonially reserved for the Emperor) over confiscation of church property. Michael was so enfuriated that he planned a rebellion to overthrow the Emperor and claim the Imperial Throne for himself. He started wearing the Imperial Regalia publicly and called for popular uprising in his sermons when he died suddenly in 1059, though there was no suspicion that he was murdered. The Emperor claimed that he was punished by God for trying to usurp his temporal powers.