Al-Mu'tasim

Born in October 796, a younger son of Harun al-Rashid, he climbed to power by recruiting Turkic ghilmān into a personal guard that his half-brother al-Ma'mun used to check rival factions. When al-Ma'mun died on campaign in August 833, he took the caliphate with backing from the chief qādī Ahmad ibn Abi Duwad and pressed ahead with Mu'tazilism and the miḥna. In 836 he founded Samarra as a new capital, centralizing control around his Turkish generals - Ashinas, Wasif, Itakh, Bugha - while sidelining the Arab and Iranian elites who had built the early Abbasid state. His general al-Afshin broke the Khurramite uprising of Babak Khorramdin by 837, then fell to court intrigue and was killed in 840. Al-Mu'tasim himself led the 838 campaign into Byzantine territory, defeated Emperor Theophilos, and razed Amorium - a victory that became the jewel of his propaganda. He died on 5 January 842, leaving a caliphate remade in the image of its mercenary army, a structure that would splinter into the chaos of Samarra and the collapse of Abbasid power within a century.