The future Patriarch Michael I Cerularius was born about the year 1000. His education was aimed for a career in the politically charged civil service, but in 1040, he was [[tonsure]]d a [[monk]]. Three years later he was appointed [[patriarch]] of the [[Church of Constantinople]] by Emperor Constantine IX (Monomachus). Michael I Cerularius, with political pretensions, became patriarch during an era in which there were numerous tensions between the Churches in the east and west, including jurisdictional disputes in the Balkans, southern Italy, and Sicily. Added to this were disputes over differing church practices as well as the claims by the Patriarchs of Rome that they stand at a higher authority among the patriarchs than being ''[[primus inter pares]]'', “first among equals”. Also, Michael I was noted for disputing with Pope [[Leo IX]] over church practices where the Roman Church differed from those of Constantinople, especially over the use of unleavened bread in the [[Eucharist]].<ref>[http://www.newadvent.org/cathen/10273a.htm Michael Cærularius] - Catholic Encyclopedia article</ref>

In the spring of 1054, Leo sent a papal delegation headed by Cardinal [[Humbert of Silva Candida]] to Constantinople to formally confront Michael. They arrived in Constantinople in April 1054. The legates’ welcome was not to their liking and they left the palace abruptly, leaving a papal letter with Michael whose anger exceeded even that of the papal delegation. Michael found the seals of the letter had been tampered with and with which was included a draft of a letter that was to be read to the Constantinople population. With that Patriarch Michael refused to recognize the authority of the delegation and completely ignored their mission. <ref>John Julius Norwich. ‘‘The Normans in the South 1016-1130’’ (Longmans, Green and Co., Ltd., 1967), 102.</ref>