structural:expansion, structural:reformatting
Renewed Persian rule

Under the Parthian and Sassanid Empires, Babylon (like Assyria) became a province of these Persian Empires for nine centuries, until after AD 650. Although it was captured briefly by Trajan in AD 116 to be part of the newly conquered province of Mesopotamia, his successor Hadrian relinquished his conquests east of the Euphrates river, which became again the Roman Empire's eastern boundary.

However, Babylon maintained its own culture and people, who spoke varieties of Aramaic, and who continued to refer to their homeland as Babylon. Examples of their culture are found in the Babylonian Talmud, the Gnostic Mandaean religion, Eastern Rite Christianity and the religion of the philosopher Mani. Christianity was introduced to Mesopotamia in the 1st and 2nd centuries, and Babylon was the seat of a Bishop of the Church of the East until well after the Arab/Islamic conquest. Coins from the Parthian, Sasanian and Arabic periods excavated in Babylon demonstrate the continuity of settlement there.