The Upper Mongols, also known as the Köke Nuur Mongols or Qinghai Mongols, are ethnic Mongol people of Oirat and Khalkha origin who settled around Qinghai Lake in so-called Upper Mongolia. As part of the Khoshut Khanate of Tsaidam and the Koke Nuur they played a major role in Sino–Mongol–Tibetan politics during the 17th and 18th centuries. The Upper Mongols adopted Tibetan dress and jewelry despite still living in the traditional Mongolian ger and writing in the script.
The Tibetan kingdom was centered on the Tibetan Plateau, formed as a result of imperial expansion under the Yarlung dynasty heralded by its 33rd king, Songtsen Gampo, in the 7th century.
The empire further expanded under the 38th king, Trisong Detsen.
The 821–823 treaty concluded between the Tibetan Empire and the Tang dynasty delineated the former as being in possession of an area larger than the Tibetan Plateau, stretching east to Chang'an, west beyond .