Sack of Amorium

In 837 the Byzantine emperor Theophilos raided deep into Abbasid territory and sacked the frontier town of Zapetra, which some sources call the caliph al-Mu'tasim's birthplace. The caliph answered the next summer with one of the largest Abbasid expeditions ever sent against Byzantium, aimed at Amorium, the home city of Theophilos's family. Byzantine attempts to stop the invasion failed, and in August 838 the Abbasids besieged the city. After about two weeks, helped by a defector who pointed out a weak stretch of wall, they broke in and sacked it. Many captives were taken back to the caliphate, and forty-two officers who refused to convert were later honoured by the Orthodox Church as martyrs.

Amorium is one of the most thoroughly excavated Byzantine cities in Anatolia, with excavation teams working at the site since 1987, and archaeologists have identified destruction deposits they associate with the sack of 838. The excavations show the city was reoccupied afterwards but never regained its old importance. The siege is unusually well documented from both sides, in Arabic chronicles such as al-Tabari's and in Byzantine sources, though each shaped the story for its own audience. Historians have used it as a case study in how personal and dynastic honour drove campaigning on the Arab-Byzantine frontier.