Ferrara-Florence, Council of

   Church council of 14381439 that achieved a union of the churches (q.v.) on paper, though not in reality. In return for accepting the papacy's (q.v.) position on such crucial doctrines as papal primacy, the filioque, and use of azyma in the Eucharist, Byzantium (qq.v.) expected effective military aid against the Ottomans (q.v.), which the papacy could not provide. The Crusade that Pope Eugenius IV (qq.v.) called met utter defeat at Varna (q.v.) in 1444. Emperor John V (q.v.) and his entourage, except for Mark of Ephesus (q.v.), who refused to sign the council's decrees, were subjected to relentless hostility upon their return. By comparison, the first union of the churches at the Council of Lyons (q.v.) in 1274 achieved more practical results. Patriarch Joseph II (qq.v.) escaped direct insult by dying in Florence, but Isidore of Kiev (q.v.) was deposed and imprisoned upon his return to Moscow (q.v.) in 1440.