Uyghurs are a Turkic (not to be confused with Turkish) speaking people of Central Asia.
The definition of Central Asia is vague, but it ought to include Xinjiang, China.
Needless to say, Xinjiang doesn’t belong to China culturally and historically.
Uyghurs are a people who are a blend (for lack of a better word) of East Asian and West Asian.
They once had a mighty empire in the 8th and 9th centuries, ruling major chunks of Central and (habitable parts of) northern Asia.
Maps etc from wikipedia