'ISA IBN MUSA

died 784 nephew of the first two 'Abbasid caliphs, military leader, and at one time presumptive heir to the caliphate. The caliph as-Saffah nominated his brother al-Mansur and, after him, 'Isa, as heirs. On the accession of al-Mansur, 'Isa was governor of Kufah. The new caliph sent him to lead an army against an 'Alid revolt in Medina, apparently with the hope that he might be killed. In a series of battles, 'Isa secured al-Mansur's rule but was forced by intimidation to renounce his rights of succession to al-Mansur's son Muhammad al-Mahdi. On al-Mansur's death, 'Isa again pressed his claim and was defeated in favor of al-Mahdi's son Musa al-Hadi.