Shiwei

Mongol Shiweis were closely related to the Khitan people to their south. As a result of pressure from the west, south and south-east they never established unified, semi-sedentarized empires like their neighbors, but remained at the level of a nomadic confederation led by tribal chieftains, alternately submitting to the Turks, the Chinese and the Khitan as the political climate evolved. The Mengwu Shiwei, one of the twenty Shiwei tribes during the Tang dynasty (618-907), were called the Menggu during the Liao dynasty (907-1125) and are generally considered to be the ancestors of the Mongols of Genghis Khan. The modern Korean pronunciation of Mengwu (蒙兀) is Mong-ol (/moŋ.ol/). Mongolia is still called "Menggu" (蒙古 Měnggǔ) in Chinese today.

In describing the origin of the Shiwei, Chinese dynastic histories record that it is somewhat related to the Khitan, who were of Xianbei origin. They were local Xianbei tribes who became independent after the Xianbei state dissolved in 234 with the death of Budugen. In the Book of Wei, it is recorded that the language of the Shiwei was the same as that of the Khitan, who spoke the Khitan language; in the Book of Sui, it is claimed that the Shiwei belonged to the same kind of people as the Khitan; and in both the New Book of Tang and Old Book of Tang, it is claimed that the Shiwei were a collateral branch of the Khitan. In this sense, the Shiwei, exactly some tribes of the Shiwei, undoubtedly had some ethnic relations with the Khitan.

The Book of Sui records that the title of the northern Shiwei chieftain was Mohefu, which is the same as the Khitan title for their chieftain - Mohefu (traditional Chinese: 莫賀弗) or "Mofuhe" (traditional Chinese: 莫弗賀), which is the Chinese rendition of the title Baghatur. For example, the Khitan Mofuhe Hechen who paid tribute to the Northern Wei at Datong in 466-470 and the Khitan Mofuhe Wuyu who fled from Goguryeo and the Rouran Khaganate in 479.

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