The pioneers of Shīʿī theology seem to have begun to propagate theological views during the middle of the second/eighth century. By that time, distinct branches of the Shīʿah had emerged. All of these believed that ʿAlī b. abī Ṭālib (reigned 35-40/656–61) was the most excellent (afḍal) after the Prophet and that he should have been the caliph or imam. The party which supported his claims and the claims of his family (abl al-bayt) for the leadership of the community became known as the Shīʿah (originally shīʿat ʿAlī, the party of ʿAlī). ʿAlī did eventually attain the caliphate and was succeeded briefly by his elder son al-Hasan, whose mother was Fāṭimah, daughter of the Prophet. When al-Hasan, who was forced to abdicate by Muʿāwiyah b. abī Sufyān (reigned 41–60/661–80), died, the Shīʿah called on his brother al-Ḥusayn to lead them in revolution against Muʿāwiyah. Al-Ḥusayn did not embark on action until after the death of Muʿāwiyah, when he answered the call of his supporters in Kufa to lead them in revolution against Muʿāwiyah's son Yazīd (reigned 60–4/680–3). The revolution proved a catastrophe and al-Ḥusayn and many of his close relatives were tragically killed at Karbalāʾ by vastly superior forces as they were on their way to Kufa (61/680). Only one son of al-Ḥusayn, ʿAlī b. al-Ḥusayn (d. 95 / 713–4), survived this disaster, and for the rest of his life he seems to have followed a quiescent policy towards the Umayyad authorities.