This dynasty is the subject of the final volumes of the history Meadows of Gold.
This dynasty is the subject of the final volumes of the history Meadows of Gold. Civil war consumed it during the Anarchy at Samarra. This dynasty legendarily sent a clock that performed magic tricks every hour to a European king. A ruler of this dynasty employed such advisers as Ja'far ibn Yahya, a Barmakid. It secured its power by winning the Battle of the Zab and defeating the (*) Tang Dynasty at the battle of the Talas River. This dynasty employed the author of the book that coined the word "algebra", who worked in the House of Wisdom established by one of its rulers, Harun al-Rashid. It moved to Cairo after Hulagu Khan and the Mongols sacked this dynasty's capital of Baghdad in 1258. For 10 points, name this Islamic caliphate that followed the Umayyads.
This dynasty is the subject of the final volumes of the history Meadows of Gold.
Abbasids [or Abbasid Caliphate]