Xiongnu. The fact that there were Wuhuan groups, who were part of the Donghu federation and followed Tuyühu Khan in the westward migration, would make the interpretation that "Tangut" represented "the Donghu people" stronger, not only from reflecting that the Wuhuan joined the Xianbei in the Tuyühu and Western Xia empires, but also contrasting that the Mongols had descended from the Xiongnu. If the Mongols had descended from the Xianbei, as the Chinese scholars characterized, the Mongols would have shared the same ethnic origins with the Xianbei of the Tuyühu Empire and not have called them as "the Donghu people" in reference of Western Xia. While the intimate associations between the two groups were manifested in the cross references of the Mongols as "Mengwu Shiwei" (or "Mongol Xianbei") from the first century and the Monguor as "Chaghan (or White) Monguor" in the thirteenth century, ethnically and culturally they remained different. As much as the prefix "Mengwu" (or "Mongol") in front of "Shiwei" (or "Xianbei") marked the difference between the Mongols and the Xianbei, the prefix "Chaghan" in front of "Monguor" indicated that the Monguor and their Xianbei predecessors were not the same as the Mongols. Culturally, the Mongols have retained a nomadic lifestyle, whereas the social organizations and religious lives of the Monguor are of far greater complexities. Mongols, Khitans, and Jurchens When the Mongols emerged as a mighty power in the thirteenth century, a reverse occurred in the ethnonyms of the Xianbei and Mongols. This was represented in the reference of the Xianbei descendants as "Chaghan Monguor" (or "White Mongols"), which gave rise to the ethnonym of "Monguor" known in the Western publications. The term "White Mongols," or "Bai Menggu," first occurred when Genghis Khan united the Mongols to rise up in Mongolia in 1206. The Xianbei descendants who resided near Mt. Yin self-proclaimed to be "White Mongols" and joined them. They received the same treatment as the Mongols and partook in their westward conquests in Central Asia and Europe. As waves and waves of the Xianbei went south and westward to establish different empires, those who remained in the northeast emerged as major powers later to rule over China. While the "Mongol Xianbei" (or "Mengwu Shiwei") emerged from the northern Manchuria and northeastern Mongolia, the Khitans, or "Qidan" in Chinese, derived their ancestral origins from the Yuwen Xianbei in southern Mongolia, who had earlier founded the Western Wei