In the first year of the Tang Dynasty (88 1 year), Tuoba Sigong occupied Zhou Xia (now Hengshan County in northern Shaanxi), which made it difficult for us to save time and make Xia Guogong independent from generation to generation. 1038 when People's Republic of China (PRC) was founded, it was named "Daxia" with Xia as its national title. Because in the west, the Song people called it "Xixia".
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Tangut, the ancestor of Xixia, originally lived in Songpan Plateau, Sichuan, and moved to northern Shaanxi in the Tang Dynasty. Because of his achievements in quelling chaos, he was appointed as our special envoy to Zhou Xia by the Emperor of the Tang Dynasty and surrendered to the Tang Dynasty, the Five Dynasties and the Song Dynasty. After the Northern Song Dynasty annexed the political power, it was re-established because Li refused to surrender and was named Emperor Liao. Through the connection between Liao and Song, Li successively occupied Lanzhou and Hexi Corridor. In the first year of Song Baoyuan (1038), Li Yuanhao proclaimed himself emperor and founded the country, that is, Xia and Xixia were formally founded.
He stood with the Northern Song Dynasty, Liao Dynasty, Southern Song Dynasty and Jin Dingzu. We divide it into two periods: the period from Xia Jingzong Yuanhao to Chongzong Ganshun is the former dynasty, that is, the Northern Song Dynasty and the Liao Ding Dynasty; Renzong Renxiao ascended the throne, and the end of Xixia was the later dynasty, that is, the period of confrontation with the Southern Song Dynasty and the Jin Dynasty.
Baidu encyclopedia-Xixia