Arbayistan was a Sassanid Persian satrapy in Late Antiquity, which reached across Upper Mesopotamia toward the Khabur river and north to the lower districts of Armenia. The area was a constant area of contention between Rome (and later the Byzantines) and the Sassanids, who fought over Mesopotamia.
- The Cambridge History of Iran, vol. 3(2): The Seleucid, Parthian, and Sasanian Periods, ed. Ehsan Yarshater (NY: Cambridge UP, 1983), 761-762.