A schism provoked by Photius (c. 815-97), Patriarch of Constantinople, that paved the way for the Eastern Schism in the thirteenth century. When Ignatius, the incumbent Patriarch of Constantinople, rebuked the vices of Bardas, co-regent under Emperor Michael III, the prelate was deposed, and Photius, a layman, was ordained priest and bishop to replace him in A.D. 857. Pope Nicholas I excommunicated Photius, who meantime charged Rome with heresy for inserting the phrase Filioque (and from the Son) into the Creed. When Emperor Michael died, his successor deposed Photius and restored Ignatius. Both actions were endorsed by the eighth ecumenical Fourth Council of Constantinople, 869-70, which is the first general council, no longer accepted by the Eastern Orthodox.