An E.-Syr. bishopric seat the heartland of which was the region extending from the small Khabur river to the Tigris, including the area of modern Zakho and part of Dehok. Administratively, it was under the jurisdiction of the metr. see of Adiabene established at the synod of 410. By the middle of the 6th cent. the diocese included the important plain of Nineveh, a more or less triangular region confined between the Tigris, the Upper Zab, the Khāzir, and the Gomal. After the expansion of the Syr. Orth. community in the plain of Nineveh during the same century and the creation of their own Beth Nuhadra, the E.-Syr. diocese was restricted to the northern and the eastern regions of its former domain. The E.-Syr. bishops are attested from the early 5th to the middle of the 13th cent. The bishops of the Syr. Orth. Beth Nuhadra are known between the end of the 6th cent. and the 8th cent., residing first in the Monastery of Nardos (modern Dayr Jundī) and then in Maʿalta. In modern times, the reduced Beth Nuhadra is the domain of the Chald. bp. who resides in Zakho.