1. Syriac Diocese, which has had Catholic bishops since 1888, now directly subject to the Syrian Antiochene Patriarch.

Its territory extends partly under Turkish rule and partly in Syria. It has 8,600 faithful, 6 provided parishes, 26 priests, 9 chapels, and 13 schools.
2. Armenian Diocese. There has been a Catholic bishop here since 1708. The present one, due to difficulties arising from Turkish legislation, resides in Baghdad. The diocese has 5 parishes, 3 churches, 7 priests, and 2,900 faithful.
3. Chaldean Diocese, since 1553. Today it is ruined and without a bishop because of Turkish policy. There remain 1 church, 1 priest, and 400 faithful.
4. Mission. Bishop Egamnon, converted from Nestorianism and appointed Chaldean bishop of M. in 1683, invited the Capuchins to the city.
This first Capuchin mission lasted until 1800, the year in which the last missionary, Fr. Ignatius, died. The mission was resumed by the same Order in 1842. The Capuchins worked with great zeal and success in the care of souls among the Jacobites, Nestorians, and Armenians, maintaining a school for boys, while the Franciscan Sisters directed one for girls. The mission was destroyed during the war of 1914–18.