Nestorius sought to defend himself at the Council of Ephesus in 431, but instead found himself formally condemned for heresy by a majority of the bishops and was subsequently removed from his see. On his own request, he retired to his former monastery, in or near Antioch. In 435, Theodosius II sent him into exile in Upper Egypt, where he lived on until 450, strenuously defending his views. His last major defender within the Roman Empire, Theodoret of Cyrrhus, finally agreed to anathematize him in 451 during the Council of Chalcedon.