The Eastern and Western churches had become increasingly estranged from the 5h century onwards. Doctrinal divisions were reflected in growing cultural divisions. In the Byzantine church the head of state was also head of the church – irreconcilable with the independence (at least in aspiration) of the papacy. Pope Leo XII cited the Donation of Constantine, which asserted the doctrinal supremacy of Rome. When a papal delegation set out to Constantinople, Michael Cerularius, patriarch of the city, refused to meet the delegates. The leader, Cardinal Humbert of Silva Candida, melodramatically entered the church of Hagia Sofia and left a Bull of Excommunication against the patriarch on the altar. In retaliation, a Byzantine synod anathematized the three papal legates. These were empty gestures, but the rift persisted, and subsequent events exacerbated matters. In 1182 the “massacre of the Latins” in Constantinople outraged the western church, and would help to precipitate the sack of Constantinople in 1204 by western crusaders. Despite several attempts at rapprochement, the schism has not healed.
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