Yesü Möngke was head of the ulus of the Chagatai Khanate

Chagatai Khanate

The Chagatai Khanate was a Turko-Mongol khanate that comprised the lands ruled by Chagatai Khan , second son of the Great Khan Genghis Khan, and his descendents and successors...

 (1246 or 1247-1252). He was the son of Chagatai Khan

Chagatai Khan

Chagatai Khan was the second son of Genghis Khan and first khan and origin of the names of the Chagatai Khanate, Chagatai language and Chagatai Turks....

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In or around 1246, he was appointed as khan of the Chagatai Khanate by his cousin the Great Khan Güyük Khan

Güyük Khan

Güyük was the third Great Khan of the Mongol Empire. As the eldest son of Ögedei Khan and a grandson of Genghis Khan, he reigned from 1246 to 1248...

, whom he was friends with, following the deposition of Qara Hülëgü

Qara Hülëgü

Qara Hülëgü was head of the ulus of the Chagatai Khanate . He was the son of Mö'etüken, and a grandson of Chagatai Khan....

. The next Great Khan, however, Möngke Khan

Möngke Khan

Möngke Khan , born Möngke, , was the fourth Great Khan of the Mongol Empire from July 1, 1251 – August 11, 1259. He was the first Great Khan from the Toluid line, and made significant reforms to improve the administration of the Empire during his reign...

, initiated a purge of the supporters of the house of Ögedei Khan

Ögedei Khan

Ögedei Khan, born Ögedei was the third son of Genghis Khan and second Great Khan of the Mongol Empire by succeeding his father...

, amongst which were the Chaghadaids. Yesü Möngke and the Chaghadaid prince Büri

Büri

Buri was a son of Mutugen and a grandson of Chagatai khan. His name - Buri - means Wolf. According to Rashid-al-Din Hamadani, Buri's mother was a wife of Chagatai khan's one official. She was a beauty, and Mutuken was attracted by her while she served in Khan's ger. Mutuken made her pregnant...

 were both exiled by Möngke to the camp of Batu Khan

Batu Khan

Batu Khan was a Mongol ruler and founder of the Ulus of Jochi , the sub-khanate of the Mongol Empire. Batu was a son of Jochi and grandson of Genghis Khan. His ulus was the chief state of the Golden Horde , which ruled Rus and the Caucasus for around 250 years, after also destroying the armies...

 of the Blue Horde, who executed them. Qara Hülëgü was then restored to his former position.