Edited sentence: A few decades later, these people spoke thus spoke Uighur Turkish, but also had a private household language, presumably Tocharian.EMPIRE OF THE STEPPES by Rene Grousset indicates that the Indo-European or Aryan peoples of Chinese Turkestan were defeated in the 7th Century during a very ill-conceived revolt against China.EMPIRE OF THE STEPPES points out that the Tocharians and Uighurs were once Buddhist (though the Uighurs were once also Manicheans).However, the decendents of both these peoples were later Islamized.Many of these people even today show red or blonde hair, as an example.Meanwhile, the Uighur Turks had been driven out of Mongolia by a more savage Turkic people, the Kirghiz.The Tocharians seem to be among the ancestors of the Uighurs who live in the same region today.The Uighurs moved to the Tocharian areas, took up a farming rather than a nomadic lifestyle, and intermarried with the local Tocharians.The book takes the position that the military defeat at the hands of China, the Uighur immigration and finally the conversion to Islam caused these people to forget the Tocharian past, though they still carry the Tocharian ancestry itself.The old Aryan/Turkic ancestry, and Muslim culture, are big political factors in the region today, causing much friction with the vast Chinese Han majority, as the Uighurs of the region have more in common with the Muslim world than with China, at least culturally.Their defeat resulted in the destruction of their nobility via military disaster