Mihna

Period of religious persecution instituted by the 'Abbasid Caliph al-Ma'mun

The Mihna was a period of religious persecution instituted by the Abbasid caliph al-Ma'mun in 833 CE in which religious scholars were punished, imprisoned, or even killed unless they conformed to Muʿtazila doctrine. The policy lasted for eighteen years as it continued through the reigns of al-Ma'mun's immediate successors, al-Mu'tasim and al-Wathiq, and four years of al-Mutawakkil who reversed it in 851.

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