In the last years of the Sui Dynasty, the tyranny of the Sui Dynasty led to the people's lack of livelihood, coupled with the failure of the military crusade against Goguryeo, and the successive years of conquests led to uprisings throughout China, whether it was warlords and nobles, or ordinary citizens, who rose up against the Sui Dynasty.
Some of the most famous rebel forces were the Wagang Village established by Li Mi, the Tianxing regime established by the Sui dynasty general Liu Wuzhou, the Caozhou regime established by Meng Haigong, and the Tang regime established by Li Yuan, the Duke of Tang.
In 618, the Jiangdu Mutiny, the Sui Emperor was killed by Yu Wenhua and his rebellious subordinates. After several years of internecine warfare among the rebel forces, only three regimes remained, namely the Tang Dynasty, led by Li Yuan, who had already proclaimed himself emperor in Chang'an, Wang Shichong, who had proclaimed himself king of Luoyang in Luoyang, and Dou Jiande in Hebei.
To say that this Dou Jiande is also a character, whenever he attacks the town to defeat the opponent, all the financial parts obtained are given to the generals, and he does not take anything himself, Dou Jiande's wife does not wear silk supplies, and there are very few slaves in the palace, he awards the position of general of the rebel army by virtue of his personal strength, so he is loved by his subordinates.
In February of the fourth year of Wu De (621), Tang Gaozu Li Yuan sent Li Shimin, the King of Qin, to lead the Tang army to attack Wang Shichong's forces in Luoyang, and Wang Shichong hurriedly asked Dou Jiande for help, so Dou Jiande personally led a large army to rescue Wang Shichong. However, Dou Jiande and Wang Shichong were not rivals to Li Shimin, dou Jiande was captured, and wang Shichong also opened the city gates and surrendered.
In July, Li Shiming escorted Dou Jiande to Chang'an, where Li Yuan ordered the beheading at the age of forty-nine.
Li Yuan's move was really confusing, because at that time, he did not kill Wang Shichong, but killed Dou Jiande, who had always been known for his virtuousness. This move laid the foundation for the subsequent regime turmoil in the Tang Dynasty.
At that time, Dou Jiande had a large number of contacts, many people were attached to him, and many areas such as Hebei were controlled by Dou Jiande's old generals, Dou Jiande was captured, and the Tang Dynasty began to persuade Dou to surrender the remnants of his forces. These generals also wanted to surrender, who knew that in just one month, Dou Jiande was directly beheaded in Chang'an, which could not help but make Dou Jiande's subordinates begin to worry about the fate of their surrender.
Among them, Dou Jiande's subordinates Liu Heimin, Fan Yuan, and others believed that surrendering to Tang was likely to be killed by Li Yuan's old tricks, and it was better to pull his own chassis and continue to oppose the Tang Dynasty. So Liu Heimin led Dou Jiande's old troops, claiming to be the King of Handong, and openly rebelled against the Tang court.
Liu Heimin was also a fierce character, having previously followed Dou Jiande in the Southern Expedition to the North, with excellent command skills, in August 621, Liu Heimin captured Liting, and the Tang Dynasty general Wang Xingmin was killed. In September of the same year, Liu Heimin defeated Luo Yi, the governor of Youzhou, and in October he immediately captured Yingzhou Guanzhou. In December, Jizhou was captured, and the Turkic Jili Khan also sent troops to assist Liu Heimin.
In less than half a year, Liu Heimin's army was like a bamboo, and the Tang Dynasty instantly lost a small half of its territory, and even had the danger of subjugation. This frightened the entire government and the public, but fortunately, Li Shimin, the King of Qin, and Li Yuanji, the King of Qi, led the main forces of the Tang Dynasty to arrive, and after half a year of fighting, they eliminated Liu Heimin's forces.
If Li Yuan had not been in a hurry to kill Dou Jiande, I am afraid that Liu Heimin and others would have been obedient, and the Tang Dynasty would not have needed to make a big move and lose soldiers.