Jamukha

Jamuqa (could also be spelled Jamuka, Djamugha or Yamuqa or similar) was a Mongol military and political leader and the chief rival to Temüjin, later Genghis Khan, in the unification of the Mongol tribes. Born in the Jadirat, a sub-tribe of the Mongols, Jamuqa was a childhood friend and a "blood brother" to Temüjin.

When Borte, wife of Temüjin, was abducted by the Merkit tribe, Wang Khan, Jamuqa and Temüjin combined forces against the Merkits to recover her.

In 1201, a kurultai elected Jamuqa as Gur Khan, "universal ruler", a title used by the rulers of the Kara-Khitan Khanate. Jamuqa's assumption of this title was the final breach between Temüjin and Jamuqa, leading Temüjin to form a coalition of tribes to oppose him.

Jamuqa was less successful in coalition-building because, unlike Temüjin, he maintained traditional divisions between tribes in his forces and assigned commands by hereditary rank rather than merit. In particular, Jamuqa did not recruit shepherds who lacked tribal status in the Mongol tradition. This allowed Temüjin to recover from a series of military defeats inflicted by Jamuqa and to emerge victorious.

Jamuqa was eventually betrayed to Temüjin by his followers in 1206. Temüjin executed Jamuqa's betrayers on the principle that betrayal merits the harshest punishment. "The Secret History of the Mongols" states that Temüjin offered renewal of their brotherhood, but Jamuqa insisted that just as there was room for only one sun in the sky, there was room only for one Mongol lord. So he asked to be executed by a noble death without spilling blood. His request was granted by having his back broken by Temüjin's soldiers.

References

[http://ideas.union.edu/articles/files/22_Stevens_Heirs_to_Discord.pdf Heirs to Discord: The Supratribal Aspirations of Jamuqa, Toghrul, and Temüjin]