Saint Cyril of Alexandria (c. 376 – 444) was the Patriarch of Alexandria from 412 to 444. He wrote extensively and was a leading protagonist in the struggle against the Nestorian heresy, which denied the Incarnation and that Our Lady is the mother of God. Saint Cyril triumphed over this heresy by his intrepidity and courage, being unafraid to denounce the errors within the clergy of his time. He was a central figure in the Council of Ephesus in 431, which led to the deposition of Nestorius, the proposer of this heresy, as Patriarch of Constantinople. It was at this council that the dogma of the Divine Motherhood of Mary, that is, that she is the Mother of God (Theotokos), was declared. After the triumph over Nestorianism, Saint Cyril spent the remainder of his days maintaining the faith of the Church and labouring for his flock.