Al-Mutasim billah was the eighth Abbasid caliph, ruling from 833 until his death in 842. A younger son of Caliph Harun al-Rashid, he rose to prominence through his formation of a private army composed predominantly of Turkish slave-soldiers (Gilman).
Al-Mu'tasim continued many of his brother's policies, such as the partnership with the Tahirids, who ruled Khurasan and Baghdad on behalf of the Abbasids. With the support of the powerful chief qadi, Ahmad ibn Abi Duwad, he continued to implement the rationalist Islamic doctrine of Mutazilism and the persecution of its opponents through the inquisition (mihna).
His reign marks a departure and a watershed moment in Islamic history, with the creation of a new regime centred on the military, and particularly his Turkish guard. In 836, a new capital was established at Samarra to symbolize this new regime and remove it from the restive populace of Baghdad.
Depicted here is a Silver dirham coin of al-Mutasim minted at al-Muhammadiya in 836/7.
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