. . Old Uyghur evolved from
Old Turkic, a
Siberian Turkic language, after the
Uyghur Khaganate broke up and remnants of it migrated to
Turfan, Qomul (later
Hami), and
Gansu in the ninth century. The Uyghurs in Turfan and Qomul founded Qocho and adopted
Manichaeism and
Buddhism as their religions, while those in Gansu first founded the
Ganzhou Uyghur Kingdom and became subjects of the
Western Xia; their descendants are the
Yugurs of Gansu. The
Western Yugur language is the descendant of Old Uyghur. The Kingdom of Qocho survived as a client state of the
Mongol Empire but was conquered by the Muslim
Chagatai Khanate, which conquered Turfan and Qomul and
Islamized the region. Old Uyghur then became extinct in Turfan and Qomul. The
Uyghur language that is the official language of the
Xinjiang Uyghur Autonomous Region is not descended from Old Uyghur. It is a descendant of the
Karluk languages spoken in the
Kara-Khanid Khanate, in particular the
Khākānī language described by
Mahmud al-Kashgari. The only surviving descendant of Old Uyghur is
Yellow Yughur, spoken in the
Gansu region of China. ==Features==