Answer:
Xinjiang is a Chinese province where around half the population are Muslim Uyghurs, a Turkic people that is ethnically close to other Turkic peoples like Uzbeks or Azeris, and the other half is Han Chinese, the predominant ethnic group in China.
The conflict in this region is cultural simply because the cultures of the Han Chinese and the Uyghurs are vastly different. For one, the Han Chinese are mostly atheists, while the Uyghurs are fervent Muslims. A second difference is language, and a third difference even arises in physical appearance, with the Uyghurs looking more like a mixture between Turkic Peoples and East Asian Peoples.