The Tanguts and The Mongols
After Renzong's death, Emperor Huanzong of Western Xia came into power and Western Xia's power began to fail. After Genghis Khan unified the northern grasslands of Mongolia, the Xianbei 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. During this period, the Mongol troops led by Genghis carried out six rounds of attacks against Western Xia over a period of twenty-two years (1202, 1207, 1209–10, 1211–13, 1214–19, 1225–26).
In 1206, Xiangzong (Li An-chuan) initiated a coup d'état against Huanzong and killed him, installing himself as emperor. In 1207 Li An-ch'uan submitted to the Mongols, and gave his daughter to Genghis Khan in marriage. Xiangzong then began a decade-long campaign against the Jin Empire, significantly weakening both empires. Also during Xiangzong's reign, corruption rose to new heights, and the peasants were in poverty. The Western Xia army was also untrained and ill-equipped. Xiangzong abdicated after Shenzong started a coup d'état and seized power, and Xiangzong died in the same year, 1211.
The Mongols asked their allies and tributaries for military aid in the campaign against the Islamic countries in 1216. Although the Tangut emperor Shenzong was willing, his court and, in particular, his general Aša-gambu, recommended against it. When Genghis Khan returned from his campaign the new emperor Xianzong pled with him, but the general Aša-gambu challenged Genghis Khan. The emperor Xianzong died during the fighting and was succeeded by Modi (Li Xian), the last of the Tangut rulers. Modi sued for peace, which was accepted, but he was then executed by Tolui, a son of Genghis Khan. (cf. Kwanten 1974).
In 1221–1222 (time of Karma Pakshi) a Karma Kagyu Lama, Tsangpa Tungkhur-wa, was invited to Minyak, which by this time had become largely Buddhist and Tibetanized. He was still there when Genghis Khan died in 1227 and he received an edict of approval from the queen.
During the last round of the Mongol attacks, Genghis died in Western Xia. The official account of the Mongol history attributed his death to an illness, whereas legends accounted that he died from a wound inflicted in the battles. After the Western Xia capital was overrun in 1227, the Mongols devastated its buildings and written records, killed the last emperor and massacred tens of thousands of civilians—effectively bringing the state to an end.
Thereafter, the Western Xia troops were incorporated into the Mongol army in their subsequent military conquests in central and southern China. Due to the fierce resistance of the Xia against the Mongol attacks, especially in causing the death of Genghis, the Tanguts were initially suppressed in the Yuan Dynasty (1271–1368). Toward the middle and later phases of the Yuan, they received equivalent treatment as the ruling Mongols and attained highest offices in the Central Court. After the Yuan fell, a substantial number of the Tanguts followed the Mongols into the northern grassland. Other communities remained in China, in modern Anhui surviving well into the Ming dynasty. Members of the royal clan emigrated to western Sichuan, northern Tibet, even possibly northeast India, in some instances becoming local rulers.
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