Kök Bayraq means "blue flag" or "blue banner" in Crimean Tatar and Uyghur. It may refer to: The flag of the Crimean People's Republic (1917–1918), now widely used to represent Crimean Tatars in general The flag of the First East Turkestan Republic (1933–1934), now widely used to represent East Turkestan or Uyghurs in general