Anbar was originally called Firuz Shapur, or Perisapora and was founded circa 350 AD by Shapur II, Sassanid king of Persia. Perisapora was captured and destroyed by Emperor Julian in 363, but speedily rebuilt. The town became a refuge for the Arab, Christian, and Jewish colonies of that region.
The Arabs changed the name of the town to Anbar ("granaries"). Abu al-Abbas as-Saffah, the founder of the Abbasid caliphate, made it his capital, and such it remained until the founding of Baghdad in 762.
It continued to be a place of much importance throughout the Abbasid period, but now it is entirely deserted, occupied only by ruin mounds. The great number of these indicates the former importance of the city.