Dingnan Jiedushi

Dingnan Jiedushi (定難節度使) — i.e., military governor (Jiedushi) of Dingnan Circuit (定難, headquartered in modern Yulin, Shaanxi) — was a political office that existed during the late Tang Dynasty, the entire Five Dynasties and Ten Kingdoms Period, and early Song Dynasty of China. Its rulers, starting from the very first military governor of Dingnan, Li Sigong (né Tuoba Sigong), were of Dangxiang ethnicity, and while the relationships between the subsequent military governors were not completely clear from historical accounts, they all stemmed from Li Sigong's clan, and the clan effectively ruled the circuit in de facto independence despite its nominal submission to the central Chinese dynasties. Attempts by Later Tang and Song to dislodge the family from its rule of Dingnan Circuit were not successful, and the region eventually evolved into the independent state of Western Xia.

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