The city was fortified by a double wall, possibly through the use of Roman prisoner labour; it was sacked and burned after an agreement with its garrison in March 363 by the Roman emperor Julian during his invasion of the Sasanian Empire. It was rebuilt by Shapur II. By 420, it is attested as a bishopric, both for the Church of the East and for the Syriac Orthodox Church. The town's garrison was Persian, but it also contained sizeable Arab and Jewish populations. Anbar was adjacent or identical to the Babylonian Jewish center of Nehardea (), and lies a short distance from the present-day town of Fallujah, formerly the Babylonian Jewish center of Pumbedita ().