During the Battle of Siffin, Ali agreed to arbitration with his challenger Mu‘awiya, but a group of Muslims who had sided with Ali in the battle argued that he should not have agreed to arbitration. For them, by agreeing to that Ali effectively relinquished legitimate power to an illegitimate ruler (Mu‘awiya). In protest, these Muslims seceded from Ali’s camp and opposed both Ali and Mu‘awiya, becoming known as Kharijis (seceders or rebels).The Kharijis held a number of politico-theological positions:They rejected the political leadership of both Ali and Mu‘awiya (and later of the Umayyads) on the basis that agreeing to arbitration by Ali was against the concept ‘judgement belongs to God alone’. They elected their own leader.