A revolt against them led by Babak, the leader of the Khorram-dinan sect, was put down by their eighth ruler, who succeeded his brother al-Mamun to the throne.  
A revolt against them led by Babak, the leader of the Khorram-dinan sect, was put down by their eighth ruler, who succeeded his brother al-Mamun to the throne.  Their first ruler was a member of the Banu Hashim who called himself the "blood-shedder" because of his fondness for killing members of the previous dynasty.  That ruler was succeeded by his brother, al-Mansur, after a brief five-year reign, having come to power at the Battle of the Great Zab with the death of Marwan II.  The last member to rule from their original capital is sometimes said to have been rolled up in a carpet and trampled to death following the 1258 sack of that capital.  Reaching their peak under the leadership of Haroun al-Rashid, FTP name this dynasty which ruled from Baghdad after supplanting the Umayyads.
A revolt against them led by Babak, the leader of the Khorram-dinan sect, was put down by their eighth ruler, who succeeded his brother al-Mamun to the throne.  
Abbasids