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 invasion of the Latin Empire mission was a renewal of submission, since a new khan had been elected since 1242. The Latin Empire is not listed by William of Rubruck among the tributaries of the Mongol Empire, however, nor was Baldwin II excommunicated for accepting Mongol overlordship as Bohemond V of Antioch was. The Mongol invasion of the Latin Empire took place just a year before the Mongols' crushing victory over the Seljuks of Anatolia at the battle of Köse Dağ (26 June 1243). Although Baldwin II had negotiated an alliance with the Seljuks in 1241, the Byzantine emperor John III Vatatzes provided aid to