First Fitna
The First Fitna () was a civil war within the Rashidun Caliphate which resulted in the overthrowing of the Rashidun caliphs and the establishment of the Umayyad dynasty. It began when the caliph Uthman was assassinated by rebels in 656 and continued through the four-year reign of Uthman's successor, Ali. It ended in 661 when Ali's heir Hasan ibn Ali concluded a treaty acknowledging the rule of Muawiyah, the first Umayyad caliph.