Hieromartyr Proterius of Alexandria (died 457), Patriarch of Alexandria (451-457), was elected by the Council of Chalcedon in 451 to replace Dioscorus of Alexandria, who had been deposed by the same council (cf. Evagrius Scholasticus, Ecclesiastical History, book 2, chapter 5[1]). His accession marks the beginning of the Schism of 451 between the Copts and the Orthodox patriarchs of Alexandria, which has never been completely resolved. Because the church of Alexandria was largely Monophysite the deposition of Dioscorus, a Monophysite, from and the elevation of Proterius, a Chalcedonian, to the Patriarchate was violently opposed. Finally in 457 the Monophysite party in Alexandria elected Timothy Aelurus as Patriarch of Alexandria, creating a parallel papacy to that of Proterius, who was sub