Adai Khan Adai ( 1390 – 1438 ) was the Mongol Khan of the Northern Yuan Dynasty in Mongolia . After the prominent eastern Mongolian chancellor , Arughtai , threw his allegiance to him , he briefly reunited most of the Mongols under his banner . Lineage and early life . The origin of Adai ’ s family lineage traced back to Kadan and Hasar due to the interfamily marriages within the Borjigin clan . Mongolian sources also say Adai was a son of Örüg Temür Khan . Adai ’ s family was a member of eastern Mongol clans , Khorchin , originated in the region of Nen River to the east of Greater Khingan Range . Even before his proclamation as the Khagan , Adai almost succeeded in unifying western Mongol territory by defeating the Oirats . Alarmed by the possible resurgence of another Genghis Khan ’ s era , the Ming Dynasty provided support to the Oirats and their allies among the western Mongol clans , successfully turning the tide by first recovering and then launching counteroffensives against eastern and central Mongol clans . Arughtai chingsang installed Adai on the throne as Khagan of the Great Yuan after discussing the matter with the family of Khasar . Reign . During his rule , Adai was able to consolidate and expand his power , eventually unifying both the central and eastern Mongol territories in 1425 . However , his conquest of western Mongol territory was checked by the Oirats and both sided continued the war for unification for decades . Riding on the success of unifying central and eastern Mongol territories , Adai proclaimed himself as Khagan with support of central and eastern Mongol clans in 1425 , the same year his rivalry khan in the west , Oyiradai was killed . Adai and Arughtai crushed the Oirats and killed several leaders of them . After capturing the Oirat nobles , Adai , married Gulichi ' s wife , Öljeitü the Beauty , who had been a consort of Elbeg Khan ( r . 1392 – 1399 ) and enslaved Bahamu ' s son ( future Toghan taishi ) . Although Adai Khan ’ s authority did not fully reach western Mongols who did not recognize him as supreme ruler , western Mongol clans did not have a khan of their own so Adai Khan remained as the sole Mongol ruler for the next eight years at least in name . Elbeg ' s daughter and the Oirat taishi Bahamu ' s widow , Samar , persuaded the Khan to release her son now named Toghan to western Mongolia . However , in 1433 , Toghan raised a rebellion and western Mongols finally crowned Toghtoa Bukha ( or Toγtoγa Buqa ) with the title of Tayisung Khan as their next new khan , which resulted in half a decade of the simultaneous existence of two khans supported by opposing Mongol clans . After two decisive campaigns in 1422 and 1423 , Adai Khan lost all of the territory gained in the past and in 1430 , the third Oirat victory wiped out his major strength , after which he could no longer mount any effective offensives and was forced on the defensive . Both sides attempted to utilize the stalemate to prepare for the next stage but Adai Khan could not recover from the previous loss . The Oirats soon launched another round of offensives and in the fourth decisive Oirat victory in 1434 in which Adai Khan ’ s major advisors , Arughtai and others , were killed , Adai Khan ’ s downfall was certain . Death . In 1438 , Adai Khan was defeated in Ejene when his territory was overran by the Oirats and their allies . Adai sought refuge in the Eight White Tents of Genghis Khan , however , being unarmed , he was murdered by Toghan taishi of the Oirat .