|Biographical detail : || The son of Rukn-ud-Dawlah, he was the greatest Buwayhid ruler.
He was the first Muslim ruler to bear the title of Shahanshah. He built the shrine on the tomb of Hazrat Ali and also the famous hospital in Baghdad called al Bimaristan. The Buwayhids ruled from 945 to 1055. During this period the Abbasid Kings were only nominal Caliphs. Tughril Beg Seljuqi drove out the last Buwayhid ruler from Baghdad.