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.
Turpan
In 803, the Uyghurs of the Uyghur Khaganate seized Turfan from the Tibetans. The Uyghur Khaganate however was destroyed by the Kirghiz and its capital Ordu-Baliq in Mongolia sacked in 840. The defeat resulted in the mass movement of the Uyghurs out of Mongolia and their dispersal into Gansu and Central Asia, and many joined other Uyghurs already present in Turfan. In the early twentieth century, a collection of some 900 Christian manuscripts dating to the ninth to the twelfth centuries was found at a monastery site at Turfan.