Li Sigong

Li Sigong (李思恭) (d. 886?), né Tuoba Sigong (拓拔思恭), formally the Duke of Xia (夏公), was an ethnically-Dangxiang warlord of the late Chinese dynasty Tang Dynasty, who, for his contributions against the major agrarian rebel Huang Chao, was allowed to retain Dingnan Circuit (定難, headquartered in modern Yulin, Shaanxi) as its military governor (Jiedushi). The position became passed down in his family, eventually forming the foundation for the Dangxiang state Western Xia of the 11th to 13th centuries.

It is not known when Tuoba Sigong was born. His family was of Dangxiang stock, of the Pingxia (平夏) branch. Late in the Xiantong (咸通) era (861–874) of Emperor Yizong, he seized control of You Prefecture (宥州, in modern Ordos, Inner Mongolia), which had been established by the Tang imperial government to govern the Dangxiang, and he claimed the title of prefect.

Around new year 881, during the reign of Emperor Xizong, the major agrarian rebel Huang Chao attacked and captured the Tang imperial capital Chang'an, forcing Emperor Xizong to flee to Chengdu. Huang established a new state of Qi as its emperor. A number of Tang generals near Chang'an gathered their troops to prepare to attack Huang to recapture Chang'an. Tuoba Sigong gathered his own troops and went to Fu Prefecture (鄜州, in modern Yan'an, Shaanxi) to rendezvous with Li Xiaochang (李孝昌) the military governor of Fuyan Circuit (鄜延, headquartered at Fu Prefecture). They swore an oath to attack Huang, and subsequently advanced south toward Chang'an. In light of Tuoba Sigong's display of loyalty, Emperor Xizong made him the acting military governor of Xiasui Circuit (夏綏).

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