Mongol Empire What is referred to in English as the Mongol Empire was called the "Ikh Mongol Uls" ("ikh": "great", "uls": "state"; Great Mongolian State). In the 1240s, one of Genghis's descendants, Güyük Khan, wrote a letter to Pope Innocent IV which used the preamble "Dalai (great/oceanic) Khagan of the great Mongolian state (ulus)". After the succession war between Kublai Khan and his brother Ariq Böke, Ariq limited Kublai's power to the eastern part of the empire. Kublai officially issued an imperial edict on 18 December 1271 to name the country Great Yuan ("Dai Yuan", or "Dai Ön Ulus") to establish the
Mongol Empire rule Persia and Mongol-held China respecively. In the southern part of the empire he continued his predecessors' struggle against the Song dynasty. In order to outflank the Song from three directions, Möngke dispatched Mongol armies under his brother Kublai to Yunnan, and under his uncle Iyeku to subdue Korea and pressure the Song from that direction as well. Kublai conquered the Dali Kingdom in 1253 after the Dali King Duan Xingzhi defected to the Mongols and helped them conquer the rest of Yunnan. Möngke's general Qoridai stabilized his control over Tibet, inducing leading monasteries to submit to Mongol rule. Subutai's