Kharkhul (English name:Khara Khula; died 1634) was a Choros-Oirat prince and tayishi of the Choros tribe. He is best known for forming and leading a coalition of the Four Oirats in battle against Ubasi Khun Tayishi, the Khalkha prince who ruled the Altan Khanate in present-day northwest Mongolia.
At the beginning of the 17th century, the Oirat tribes were roaming the pastureland between the Irtysh and the Ili rivers. They were pressured to migrate west to that area from their home in the Altai Mountains by Ubasi Khun Tayishi who was expanding his state by robbing the Oirats of their valuable pastures.
During this era, the Oirat tribes were fragmented along traditional tribal divisions, viz., Choros, Dörbet, Torghut, Khoshut, Khoit, etc. Each tribe had its own hereditary ruler. The tribes constantly competed against each other, profiting at the others' expense, while seeking to maintain their independence. This disunity had plagued the Oirats for 150 years, since the dissolution of the Dörben Oirat state after the murder of Esen Tayishi in 1454, and made them an easy opponent for Ubasi Khun Tayishi.
Around 1600, Kharkhul succeeded his father, Bulai (or Abuda Ablai Tayishi) as tayishi of the Choros tribe. Although his birth name was "Khutugaitu," his father nicknamed him Khara Khula - the name historians use to identufy him. The name describes a lion-like, dark-colored animal from the Altai Mountains that Khutugaitu supposedly killed.
As tayishi of the dominant Oirat tribe, Khara Khula emerged from his base in the upper Irtysh river and Tarbagatai Mountains region to take up the cause of the unorganized and confused Oirat tribes in their war against Ubasi Khun Tayishi. In so doing, Kharkhul's objective was to establish the political and military unity that his ancestor Esen Tayishi once demanded from the Oirat princes and, in the process, forge a new state.