Nestorius (Archbishop of Constantinople, ~428–431 AD) taught — or was accused of teaching — that the divine and human in Christ were so distinct as to constitute two persons, not one. His specific controversy was over the title Theotokos (‘God-bearer’ or ‘Mother of God’) for Mary. Nestorius preferred Christotokos (‘Christ-bearer’) — arguing that Mary gave birth to the human nature, not to the divine. Cyril of Alexandria, his opponent, insisted that because Christ is one person, Mary bore God (in the sense that she bore the one who is God). The Council of Ephesus (431 AD) condemned Nestorius. His followers fled to the Persian Sassanid Empire and established the Church of the East (often called ‘Nestorian’ though they reject the label). 20th century dialogue has clarified that Nestorius himself may not have been ‘Nestorian’ — the controversy was partly about different theological vocabularies from the Alexandrian and Antiochene schools.