Surname of Khans
The surname of Xueyantuo's khans are uncertain, although modern Chinese historian Bo Yang listed their surname as "Yishi" in his edition (also known as the Bo Yang Edition) of the Zizhi Tongjian, but Bo cited no source for his use of Yishi as a surname. It is possible that Bo was influenced by the Tongdian which asserted the Xueyantuo surname as Yilitu (壹利吐, Yiliduo 一利咄 as in Cefu Yuangui and Yilidie 壹利咥 as in New Book of Tang) or certain studies that was made.
According to Cen Zhongmian the forementioned name are related to the variant of elteris. Duan Lianqin asserted that the name Yishibo (Yiedie Khan) can also be read interchangeable as Yedie (也咥). The Zizhi Tongjian, in the original, referred to one ethnic Xueyantuo general named Duomo, possibly the Yitewushi Khan (after he became a Tang general) by the family name of Xue -- although the Tang Huiyao indicated that it was not the same person, as it indicated that the Yitewushi Khan died during Emperor Taizong's reign.
The Tang Huiyao also asserted that the rulers of Xueyantuo claimed to be originally named Xue, and that the name of the tribe was changed to Xueyantuo after the Xue defeated and merged the Yantuo into their tribe.
first, old Chinese Xue (薛) family from Chen (state) the Gui family with Region name "Xue" (薛) of Shandong, later the Yuan family of Emperor Xiaowen of Northern Wei get surname to "Xue" (薛). a last, Xueyantuo people have surname Xue/Xie (薛/偰) from Tribe name "Xue" (偰/薛), thus surnname Xue has 3 kinds of origin. see Xue Rengui (薛仁贵)
Xueyantuo, and Hui people was feudal lords of Manchuria and north Goryeo at late Yuan Dynasty period. Xie Wen Zhi (偰文質) was Public Officer at Yuan Dynasty 13th century, his son Xie Xun (偰遜), emigrate to Goryeo, Xie (偰) family merge to Xue (薛) family after Goryeo.
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