Photian schism

The Photian Schism was a four-year (863–867) schism between the episcopal sees of Rome and Constantinople.

At issue was the papal claim to jurisdiction in the East, not accusations of heresy. The schism arose largely as a struggle for ecclesiastical control of the southern Balkans and because of a personality clash between the heads of the two sees, both of whom were elected in the year 858 and both of whose reigns ended in 867, by death in the case of the Pope, by the first of two depositions for the Patriarch. The Photian Schism thus differed from what occurred in the 11th century, when the pope's authority as a first among equals was challenged on the grounds of having lost that authority through heresy.

In 858 Patriarch Ignatius of Constantinople, who had been patriarch since 847, was deported by Byzantine Emperor Michael III and his uncle the effective ruler Bardas on suspicion of being in league with their opponents, and may have formally resigned, although some historians conclude that he refused. The layman Photius was elected in his place and was hurriedly consecrated bishop within one week contrary to the canonical rules but not without precedent in Constantinople. One of the consecrating bishops was Gregory Asbestas of Syracuse, whom Ignatius had condemned and deposed. When some bishops and most of the monasteries (most notably that of Studion) refused to recognize him, Photius held a synod in 859 that declared Ignatius no longer patriarch.

In 860, Emperor Michael III invited Pope Nicholas I to send legates to a council at Constantinople which would further elucidate Catholic doctrine on icons. The Pope decided to send legates and wrote to Photius, expressing satisfaction at his orthodox profession of faith, reproving his hurried uncanonical consecration, but saying that, if the legates' examination into the conduct of Ignatius supported the accusations made, he would accept Photius as patriarch, reserving judgement to himself. Exceeding their powers and perhaps under pressure from the imperial court, the legates took part in 861 in a synod at Constantinople that ruled in favour of Photius, but Nicholas I eventually disowned their choice, and in 863 held a synod of his own in Rome, which annulled the proceedings of the 861 synod in Constantinople, condemned Photius and reinstated Ignatius.

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