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 Uyghurs believed in Shamanism and Tengrism, then Manichaeism, Buddhism and Church of the East. People in the western Tarim Basin region began to convert to Islam in significant number early in the Kara-Khanid Khanate period. There had been Christian conversions in the late 19th and early 20th centuries but these were suppressed by the First East Turkestan Republic government. Modern Uyghurs are now primarily Muslim, and they are the second largest predominantly Muslim ethnicity in China after the Hui.