The Shī'ite revolts against the Umayyads may be said to have begun in 671. Immediately after his father's death in 661, al-Ḥasan had made an unsuccessful attempt to resist Mu'āwiyah, and had then retired to a life of luxury in Medina. Ten years later there was an abortive revolt in Kūfah led by Ḥujr b. ‘Adī al-Kindī. Next, in the troubled period after the death of Mu'āwiyah in 680, al-Ḥusayn, the younger son of 'Alī and Fāṭimah, with some encouragement from the Shī'ite party in Kūfah, came to 'Irāq and claimed the caliphate. He did not receive the support he had expected, however, and his small force of about a hundred was massacred at Karbalā'. In the confusion of the following years, with considerable support in ‘Irāq for Ibn az-Zubayr, the Shī'ites remained quiet; but on the death of Yazīd in 684 some of the older Shī'ites of Kūfah, led by Sulaymān b. Ṣuraḍ al-Khuzā'ī, preparedfor military action. The basis of this movement was twofold: they were to show that they repented of the betrayal of al-Ḥusayn (and so are known as the tawwābūn or Penitents), and they were to seek vengeance for his blood. Most of those who carried out the massacre at Karbalā' were living in Kūfah, but the governor who had despatched the army against al-Ḥusayn, 'Ubaydallāh b. Ziyād, had been forced to retire from 'Irāq and was now on the Syrian border with an army. After some debate they decided to march against him with their 4,000 men, but they were defeated and several of their leaders killed (Jan., 685).