Gao Kaidao

Gao Kaidao (高開道) (died 624), at one point known as Li Kaidao (李開道), was an agrarian rebel leader who rose against Sui Dynasty rule at the end of Emperor Yang's reign. He occupied the region centering Huairong (懷戎, in modern Zhangjiakou, Hebei) and claimed the title of Prince of Yan, in alliance with Eastern Tujue. In 620, he briefly submitted to Emperor Gaozu of Tang and was bestowed the imperial surname of Li, but in 621 he rebelled against Tang and reasserted independence. In 624, his general Zhang Jinshu (張金樹) started a coup and he, realizing that the coup was about to succeed, committed suicide.

Little is known about Gao Kaidao's background, and his birth year is not known. He was from Cang Province (滄州, roughly modern Cangzhou, Hebei). In his youth, he supported himself by boiling sea water to yield salt. He was said to be strong and fast on his horse.

In or before 616, Gao joined the rebel leader Ge Qian (格謙). Ge was killed by the Sui general Yang Yichen in 616, and Gao gathered the remainder of Ge's troops. He led them in pillaging the modern northern Hebei.

In 617, Gao put Beiping (北平, in modern Qinhuangdao, Hebei) under siege—a siege that lasted for more than a year. Around the new year 619, the Sui general Li Jing (李景), who defended the city, could not defend the city any more, and abandoned it when another Sui general, Deng Gao (鄧暠), came to his aid. Gao Kaidao was then able to capture Beiping, and he then also captured Yuyang (漁陽, in modern Tianjin). He declared himself the Prince of Yan and changed the era name to show independence from Sui. He set his capital at Yuyang.

Meanwhile, there was another major rebel leader nearby—Gao Tansheng (高曇晟), a Buddhist monk who had seized Huairong and claimed the title of Dacheng Emperor (i.e., Emperor of Mahayana). Gao Tansheng sent messengers to persuade Gao Kaidao to submit to him, and Gao Kaidao agreed. Gao Tansheng created him the Prince of Qi, but several months later, Gao Kaidao assassinated Gao Tansheng, taking over Gao Tansheng's troops and making Huairong his capital. Both he and another rebel leader, Dou Jiande, tried to get Luo Yi, who then occupied You Prefecture (幽州, roughly modern Beijing), to submit, but Luo refused, submitting instead to Tang Dynasty.

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