Historical Development of The Doctrine of Papal Primacy - East-West Schism

East-West Schism

The dispute about the authority of Roman bishops reached a climax in the year 1054, when Michael I Cerularius tried to bolster his position as the Patriarch of Constantinople, seeming to set himself up as a rival of Pope Leo IX, as the popes previously had forbidden calling Constantinople a patriarchate. The disputed ended when the pope's legate excommunicated Michael I Cerularius and, in exchange, he excommunicated the pope—who by then was already dead, due to sickness. This event resulted the separation of the Churches.