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
The ancient people of the Tarim Basin originally spoke different languages such as Saka (Khotanese), Tocharian and Gandhari. The Turkic people who moved into region in the 9th century brought with them their languages which slowly supplanted the original tongues of the local inhabitants. By the 11th century, it was noted by Mahmud al-Kashgari that the Uyghurs (of Qocho) spoke a pure Turkic language, but they also still spoke another language among themselves and have two different scripts. He also noted that the people of Khotan did not know Turkic well, and have their own language and script (Khotanese). Writers of the Karakhanid period, al-Kashgari and Yusuf Balasagun, referred to their Turkic language as "Khāqāniyya" (meaning royal), or the "language of Kashgar", or simply Turkic.