Kumo Xi

The Kumo Xi (traditional Chinese: ; simplified Chinese: ; pinyin: Kùmò Xī), also known as the Tatabi, were ancient steppe people located in modern Northeast China from 207 to 907 AD. After the death of their ancestor Tadun in 207, they were no longer called Wuhuan but joined the Khitan Xianbei in submitting to the Yuwen Xianbei. Their history is closely linked to the more famous Khitan.

The Kumo Xi engaged in conflicts with numerous Chinese dynasties and with the Khitan tribes, eventually suffering a series of disastrous defeats to Chinese armies and coming under the domination of the Khitans. In 907, the Kumo Xi were completely assimilated into the Khitan-led Liao dynasty of China.