"Abū Isḥāq Muḥammad ibn Hārūn al-Rashīd (Arabic: أبو إسحاق محمد بن هارون الرشيد; October 796 – 5 January 842), better known by his regnal name al-Muʿtaṣim biʾllāh (المعتصم بالله, lit. 'He who seeks refuge in God'), was the eighth Abbasid caliph, ruling from 833 until his death in 842. A younger son of Caliph Harun al-Rashid (r. 786–809), he rose to prominence through his formation of a private army composed predominantly of Turkic slave-soldiers (ghilmān, sing. ghulām). This proved useful to his half-brother, Caliph al-Ma'mun, who employed al-Mu'tasim and his Turkish guard to counterbalance other powerful interest groups in the state, as well as employing them in campaigns against rebels and the Byzantine Empire. When al-Ma'mun died unexpectedly on campaign in August 833, al-Mu'tasim was thus well placed to succeed him, overriding the claims of al-Ma'mun's son al-Abbas." - (en.wikipedia.org 12.12.2021)
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