Kumo Xi
The Kumo Xi were descendants of the Wuhuan. The "Book of the Later Han" 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.