Diocese of the East
The Diocese of the East, also called the Diocese of Oriens (Latin: Dioecesis Orientis; Greek: Διοίκησις Ἑῴα), was a diocese of the later Roman Empire and Byzantine Empire, incorporating the provinces of the western Middle East, between the Mediterranean Sea and Mesopotamia. During Late Antiquity and the period of late antique Syria, it was one of the major commercial, agricultural, religious and intellectual areas of the empire, and its strategic location facing the Sassanid Empire and the nomadic tribes gave it exceptional military importance.