Khuzistan

Rashidun period

In 639, the Muslim Rashidun Caliphate forces under the command of the Arab Abu Musa al-Ash'ari defeated the Sassanids in Ahvaz and drove the Persian satrap Hormuzan out of the city. Susa later fell, so Hormuzan fled to Shushtar. The Muslims led by Abu Musa thereafter imposed a siege on the Sassanid forces in Shushtar that lasted for 18 months. Shushtar finally fell in 642 and the Muslims subsequently established full control over the area. The Khuzistan Chronicle records that an unknown Arab, living in the city, befriended a man in the army, and dug tunnels through the wall in return for a third of the spoil. The Arabs purged the Nestorians—the Exegete of the city and the Bishop of Hormizd, and all their students—but kept Hormuzan alive.