In 1058, Baghdad was captured by the Fatimids under the Turkish general Abu'l-Ḥārith Arslān al-Basasiri, an adherent of the Ismailis along with the 'Uqaylid Quraysh. Not long before the arrival of the Saljuqs in Baghdad, al-Basasiri petitioned to the Fatimid Imam-Caliph al-Mustansir to support him in conquering Baghdad on the Ismaili Imam's behalf. It has recently come to light that the famed Fatimid ''da'i'', al-Mu'ayyad al-Shirazi, had a direct role in supporting al-Basasiri and helped the general to succeed in taking Mawṣil, Wāsit and Kufa. Soon after, by December 1058, a Shi'i ''adhān'' (call to prayer) was implemented in Baghdad and a ''khutbah'' (sermon) was delivered in the name of the Fatimid Imam-Caliph. Despite his Shi'i inclinations, Al-Basasiri received support from Sunnis and Shi'is alike, for whom opposition to the Saljuq power was a common factor.