Emperor Tang Gaozu 中国皇帝唐高宗

The Sui Dynasty (590-618) only had two emperors. At the end of the Sui, peasant uprisings rapidly swept throughout the country due to heavy taxation and extravagance of the emperor, which made the common people suffer a lot. Furthermore, the emperor tried three times to invade the northern part of Korea but never succeeded, rapidly worsening the situation.

Li Yuan was originally an aristocrat of the Sui Dynasty. In the year 617 he was dispatched to Tai Yuan by Sui Yangdi (the Emperor Yang of the Sui Dynasty), to battle the rebellion by the peasants there. Li Shimin, the second and also the most capable among all of Li Yuan's sons, had his own plans as he was sure that Sui would not last long. Li Shimin's friend Liu Wenjing suggested that he raise troops and rebel against the Sui Dynasty. Li Shimin thought that there was something in what he suggested and persuaded his father to do so.

Li Shimin, who, at the age of sixteen, already showed his outstanding military ability, suggested his father borrow military power from a formal enemy country of the Sui dynasty -- the Hun. Li Yuan consented to his suggestion and asked Liu Wenjing to help him to recruit soldiers and increase military power.

Before long, Li Yuan left Jin Yang and headed for Chang'an together with 30,000 soldiers. On the way there, they gave rice to peasants and won their heart, which was the routing practice by the rebellious armies. After they conquered the city of Huo Yi, they crossed the Yellow River and summoned up about 200,000 people with the help from the peasant rebels from Guan Zhong. They were all ready to attack Chang'an, the capital city.