Fourth Fitna

Abbasid-era Muslim civil war (811–819)

The Fourth Fitna, Fourth Muslim Civil War, or Great Abbasid Civil War resulted from the conflict between the brothers al-Amin and al-Ma'mun over the succession to the throne of the Abbasid Caliphate. Their father, Caliph Harun al-Rashid, had named al-Amin as the first successor, but had also named al-Ma'mun as the second, with Khorasan granted to him as an appanage. Later a third son, al-Qasim, was designated as third successor.

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