• Patriarch of Alexandria 412 - 444
• central figure in the Council of Ephesus in 431
• Church Fathers
• Doctor of the Church

He was enthroned when the city was at the height of its influence and power within the Roman Empire. Cyril wrote extensively and was a leading protagonist in the Christological controversies of the late-4th and 5th centuries. He was a , which led to the deposition of Nestorius as Patriarch of Constantinople. Cyril is counted among the , and his reputation within the Christian world has resulted in his titles Pillar of Faith and Seal of all the Fathers. The Roman Emperor Theodosius II, however, condemned him for behaving like a "proud pharaoh", and the Nestorian bishops at their synod at the Council of Ephesus declared him a heretic, labelling him as a "monster, born and educated for the destruction of the church."[1]

Cyril is well known for his dispute with Nestorius and his supporter, Patriarch John of Antioch, whom Cyril excluded from the Council of Ephesus for arriving late. He is also known for his expulsion of Novatians and Jews from Alexandria and for inflaming tensions that led to the murder of the Hellenistic philosopher Hypatia by a Christian mob. Historians disagree over the extent of his responsibility in this.