Li Yuanji

Li Yuanji (李元吉) (603 – July 2, 626), formally Prince La of Chao (巢剌王), more commonly known by the title of Prince of Qi (齊王), nickname Sanhu (三胡), was an imperial prince of the Chinese Tang Dynasty. He was a son of the dynasty's founder Emperor Gaozu of Tang (Li Yuan), and in the intense rivalry developed between his older brothers Li Jiancheng the Crown Prince and Li Shimin the Prince of Qin, he sided with Li Jiancheng and often advocated drastic actions against Li Shimin, including assassination. In 626, Li Shimin, fearing that Li Jiancheng and Li Yuanji were about to kill him, laid an ambush for them at Xuanwu Gate outside the palace and killed them. Li Shimin then effectively forced Emperor Gaozu to yield the throne to him (as Emperor Taizong).

Li Yuanji was born in 603, during the reign of Emperor Wen of Sui. He was the fourth and final son of Li Yuan the Duke of Tang, a hereditary noble, and Li Yuan's wife Duchess Dou, who was herself the daughter of Dou Yi (竇毅) the Duke of Shenwu and Northern Zhou's Princess Xiangyang. He had three older brothers by Duchess Dou -- Li Jiancheng, Li Shimin, and Li Xuanba (李玄霸, who died in 614). She also gave birth to an older sister of Li Yuanji's, the eventual Princess Pingyang.

In 616, with agrarian rebellions beginning to engulf northern China and frequent Eastern Tujue incursions across the border, Emperor Yang of Sui commissioned Li Yuan to be the commander of the forces at Taiyuan, guarding it against both agrarian rebels and Eastern Tujue. At that time, Li Yuan took Li Shimin with him to Taiyuan, but left Li Jiancheng, Li Yuanji, another son Li Zhiyun (李智雲), and the rest of his household at Hedong (河東, in modern Yuncheng, Shanxi). In 617, Li Yuan, fearful that Emperor Yang might punish him for his inability to suppress the rebels led by Liu Wuzhou the Dingyang Khan, was persuaded by Li Shimin to rebel against Sui rule. He then sent secret messengers to Hedong to summon his sons and to the capital Chang'an to summon his daughter and son-in-law Chai Shao (柴紹). Li Jiancheng and Li Yuanji secretly travelled to Taiyuan, but left the 13-year-old Li Zhiyun at Hedong.

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