Mongol Empire his generals and other associates, and some Mongols who had previously been allies broke their allegiance. War ensued, and Temujin and the forces still loyal to him prevailed, defeating the remaining rival tribes between 1203 and 1205 and bringing them under his sway. In 1206, Temujin was crowned as the khagan of the "Yekhe Mongol Ulus" (Great Mongol State) at a kurultai (general assembly/council). It was there that he assumed the title of Genghis Khan (universal leader) instead of one of the old tribal titles such as Gur Khan or Tayang Khan, marking the start of the Mongol Empire. Genghis
Mongol Empire his other sons, such as Tolui, Chagatai, or Jochi. The Toluids prevailed after a bloody purge of Ögedeid and Chagataid factions, but disputes continued among the descendants of Tolui. A key reason for the split was the dispute over whether the Mongol Empire would become a sedentary, cosmopolitan empire, or would stay true to their nomadic and steppe lifestyle. After Möngke Khan died (1259), rival kurultai councils simultaneously elected different successors, the brothers Ariq Böke and Kublai Khan, who fought each other in the Toluid Civil War (1260–1264) and also dealt with challenges from the descendants of other sons of