Abu Abdallah Muhammad ibn Abdallah al-Mansur, better known by his regnal name al-Mahdi, was the third Abbasid Caliph who reigned from 775 to his death in 785. He succeeded his father, al-Mansur. WikipediaBorn: 754 AD, Ahvaz, IranDied: August 4, 785 ADSpouse: Al-KhayzuranSuccessor: Al-HadiParents: Al-Mansur