Kublai vs. Ariq Böke: War for the Khaganate

Timeline

1. 1259–1260Karakorum and Kaiping (Shangdu) · Mongolian SteppeIn 1259 the Mongol great khan Möngke died of illness during the siege of Diaoyu Fortress at Hezhou, leaving the throne suddenly vacant. Supported by the Toluid princes garrisoned at Karakorum, Ariq Böke preemptively convened a kurultai in early 1260 and was acclaimed great khan of the Great Mongol Empire. Kublai promptly convened his own kurultai at Kaiping (Shangdu), claiming the throne with the backing of Han officials and some princes, creating two rival khans and triggering the civil war.
2. 1261Simutu Naor · Mongolian SteppeIn 1261 Kublai personally led a large army north and fought Ariq Böke's forces in the first major open battle at Simutu Naor (in central Mongolia today). With ample grain supplies and elite Han troops, Kublai's forces gained a clear advantage, and Ariq Böke was forced to retreat deep into the northern steppe. The battle established Kublai's military ascendancy.
3. 1261–1262Chagatai Khanate territories · Steppe zoneAfter his defeat at Simutu Naor, Ariq Böke realized the northern steppe alone could not sustain him, so he installed his confidant Alghu as Chagatai khan, hoping to use Central Asian manpower and grain to break Kublai's supply blockade. But Alghu soon betrayed him, refusing to send supplies, cutting Ariq Böke's western route, and pledging allegiance to Kublai instead. This reversal sharply worsened Ariq Böke's strategic position.
4. 1262–1264northern Mongolian steppe · Mongolian SteppeWith western supply lines severed, Ariq Böke's army fell into severe famine; large numbers of followers fled or voluntarily defected to Kublai amid bitter cold and hunger. Kublai launched several offensives, and the princes Ariq Böke relied on defected one by one, his territory steadily shrinking. Meanwhile Kublai continued to develop North China and the Central Plains, sustaining the war with ample reserves, and the balance of power shifted irreversibly in his favor.
5. 1264Kaiping (Shangdu) · Northern ChinaIn 1264 the cornered Ariq Böke led his remaining followers to Shangdu, where Kublai was stationed, and formally submitted. Kublai pardoned Ariq Böke personally but ordered the execution of the leading princes who had supported him, marking the definitive end of the four-year civil war and making Kublai the unquestioned Mongol great khan. Ariq Böke was placed under house arrest and died around 1266. Kublai thereafter moved the capital to Dadu and formally established the Yuan dynasty in 1271, fully shifting the center of Mongol rule to the Central Plains.