Kumo Xi

The Kumo Xi (traditional Chinese: ; simplified Chinese: ; pinyin: Kùmò Xī; called the Xi since the Sui dynasty (581-618 AD)), also Tatabi, were a Mongolic steppe people located in current northeast China from 207 AD 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 widely linked to the more famous Khitan. During their history the Kumo Xi engaged in conflict with numerous Chinese dynasties and with the Khitans, eventually suffering a series of disastrous defeats to Chinese armies and coming under the domination of the Khitans. In 1007, the Kumo Xi were completely assimilated into the Khitan Liao Dynasty.

The Kumo Xi and the Khitans were united in a tribal Kumo Xi entity. In 388 AD, the previously defeated Kumo Xi leaders insisted on fighting against with the proto-Mongolic Northern Wei dynasty. When the battlefield seemed to favor Wei, the Khitans fled, leaving the Kumo Xi be crushed. The Kumo Xi were so badly weakened by their defeat to the Northern Wei that the Khitans were able to freely split from the Kumo Xi afterwards, thereby starting their own independent history.

The Kumo Xi were descendants of the Wuhuan. The Hou Hanshu records that “the language and culture of the Xianbei are the same as the Wuhuan”. Along with the Xianbei, the Wuhuan formed part of the proto-Mongolic Donghu confederation in the 4th century BC. The Weishu (Description of the Khitan, Vol. 1000, 2221) records that the Kumo Xi and Khitans (descendants of the Xianbei) spoke the same language.

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