Originating from the Khitan Mongol dynasty, the Qara-Khitai took power in Northern China and adopted the dynastic name of Liao (c. 1124-1218). Chased away on their turn by the Jürchen, the Qara Khitai or Western Liao emigrated toward Central Asia then peopled predominantly by sedentary Muslims, but did not convert to Islam contrary to the former and later conquerors of the same area. The new empire, multiethnic and heterogenic, was divided up between a central territory placed directly under the authority of the Qara Khitai and the territories of kingdoms and tribal confederations that, though subjugated, could preserve a large autonomy. According to M. Biran, contrary to the other conquerors of Central Asia the Qara Khitai found in their Chinese tradition a powerful enough tool for legitimization, and did not feel the need to conversion. The Chinese tradition of the Liao played a role often attributed by historians and anthropologists to Islam—explaining the conversion of Central Asian nomads in close connection with state-building process. As to the Qara Khitai, they enjoyed a centralised administrative tradition, a strong identity, and the prestige of their origin. They were also helped by their political know-how, characterised by a capacity to win the Muslims’ sympathy through a policy of religious ‘tolerance’ and through a just exercise of power—an intrinsically legitimating attitude in Islam. The autonomy granted to Islam and its institutions, to the subjugated kingdoms and tribes were such that the travellers of the time often ignored the very existence of the Qara Khitai. M. Biran also recalls that the subjugated Muslim populations often considered them as the defenders of Islam.