The Kharijites (, "al-Khawārij", singular , "khāriji"), also called the al-Shurat (Arabic: الشراة, "al-Shurāt"), were an Islamic sect that appeared in the first century of Islam during the First Muslim Civil War, the crisis of leadership after the murder of the third caliph Uthman. Some members of the army of the fourth caliph Ali seceded after he agreed to arbitration with his rival, Mu'awiya I, to decide the succession to the caliphate following the Battle of Siffin in July 657. They asserted that "judgment belongs to God alone" and that leaving the matter to the judgment of humans was in violation of the injunctions of the Qur'an which commanded that rebels must be fought and overcome. Ali was unsuccessful in winning back their loyalty and after their insurgent activities attacked and defeated them in the Battle of Nahrawan in July 658. Nevertheless, the Kharijites were far from eliminated and their insurrection against the caliphate continued. Ali himself fell in January 661 to a Kharijite assassin seeking revenge for Nahrawan.