Uyghurs
Contemporary scholars consider modern Uyghurs to be the descendants of a number of people, including the ancient Uyghurs of Mongolia who arrived at the Tarim Basin after the fall of the Uyghur Khaganate, Iranic Saka tribes, and other Indo-European peoples who inhabited the Tarim Basin before the arrival of the Turkic Uyghurs. DNA analyses indicate that the peoples of central Asia such as the Uyghurs are all mixed Caucasian and East Asian. Uyghur activists identify with the Tarim mummies, remains of an ancient people who inhabited the region, but research into the genetics of ancient Tarim mummies and their links with modern Uyghurs remains problematic, both to Chinese government officials concerned with ethnic separatism, and to Uyghur activists concerned that the research could affect their people's claim of being indigenous to the region.
Uyghurs in Beijing
During the Tang dynasty, the ancient Uyghur Kingdom and the Tang government had close relations and large numbers of ancient Uyghurs of Mongolia including merchants and soldiers migrated to Youzhou (modern Beijing). The Tang governor of Youzhou, Zhu Tao, who rebelled against the Tang dynasty in 783, had a Uyghur wife and 3,000 Uyghur cavalry under his command. After the Uyghur Kingdom was conquered by the Yenisei Kirghiz in 840, many Uyghurs fled south to Tang China and some 30,000 settled in Youzhou. In the Liao dynasty, Youzhou became the Southern Capital of the Liao and Uyghurs merchants lived in a part of the city known as the "Weiwuerying" or the "Uyghur Camp."