The Dzungars were a confederation of several Oirat tribes that emerged in the early 17th century to fight the Altan Khan of the Khalkha (not to be confused with the better known Altan Khan of the Tümed), the Jasaghtu Khan, and later the Manchu for dominion and control over the Mongolian people and territories. This confederation rose to power in what became known as Dzungaria between the Altai Mountains and the Ili River Valley. Initially, the confederation consisted of the Oöled, Dorbet (also written Derbet) and Khoit tribes. Later on, elements of the Khoshut and Torghut tribes were forcibly incorporated into the Dzungar military, thus completing the re-unification of the West Mongolian tribes.
According to oral history, the Oöled and Dörbed tribes are the successor tribes to the Naiman, a Mongol tribe that roamed the steppes of Central Asia during the era of Genghis Khan. The Oöled shared the clan name Choros with the Dörvöd. "Zuun gar" (left hand) and "Baruun gar" (right hand) formed the Oirat's military and administrative organization. The Dzungar Olots and Choros became the ruling clans in the 17th century.