Asuristan was a province under the Sassanid Empire (226–640 AD). It corresponds to the Babylonia province under the Parthian Empire.

The province for the most part stretched from Mosul to Adiabene. While the official religion of the Sassanid empire was Zoroastrianism, the religion of the Assyrians was, from the 1st and 2nd centuries onwards, Church of the East Christianity, although some also still worshipped the old Mesopotamian Religion, with Ashur still worshipped in his home city until at least the late 3rd century AD. Assyrians were the indigenous inhabitants, and outnumbered the Persians in the Asuristan province. The main language spoken was Aramaic. Its inhabitants were mostly working in agriculture or as traders and merchants. The city of Ctesiphon served as the capital of both the Parthian and Sassanid empires, and was at this time the largest city in the world.

The Sassanid province of Asuristan produced several unique cultural contributions to the world (all using varieties of Mesopotamian Eastern Middle Aramaic for their original scriptures):