Qaidu (1236-1301), one of the great rebels in the history of the Mongol Empire, was the grandson of gedei, the son Genghis Khan had chosen to be his heir. After Genghis' death (1226), gedei was enthroned as the Great Khan or the Qa'an, the supreme ruler of the entire Mongol Empire. The gedeids retained their position as Qa'ans in the reign of gedei's son, Qaidu's uncle, Gnynk Qa'an (1246-1248). On the latter's death, however, a power struggle ensued, which ended in 1251 with the passing of the position of the Qa'an from the house of gedei to the house of Tolui, fourth son of Genghis Khan, and with the rise of M/ngke Qa'an, son of Tolui. M/ngke's accession was accompanied by the execution and exile of a large part of the house of gedei. Qaidu, who survived M/ngke's purges, was the one who strove to revive the gedeid cause. By virtue of his political and military skills, and despite his lesser starting point, in the 1270s Qaidu succeeded in establishing a kingdom of the house of gedei in Central Asia, and in constituting a weighty adversary to Qubilai Qa'an, Mongke's brother and sucessor, and to his heirs.