Kumo Xi

The Kumo Xi, or Xi, were a nomadic people of the upper Liao River region of eastern Inner Mongolia, closely related to the Khitan and traced by Chinese sources to the Yuwen Xianbei. They were subject in turn to the Turks, the Tang and the Uyghurs, and from the 10th century were absorbed into the Khitan Liao state, where they formed a distinct part of its army and administration.