The early caliphate was not an especially stable place. In the two centuries after Muhammad’s death in 632, the empire went through four civil wars (the four fitnas, as they’re known). It’s fair to say that the second of these, which lasted from 680 to 692, was basically a do over of the first, with the same factions (the Umayyads, loyalists of Ali and his family, and those who were neither of those things) having another go at sorting out Islam’s political future.
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