Emperor Gaozu of Tang (566-635) was the founder and first emperor of this great dynasty. He was born Li Yuan, and given the courtesy name of Shude. He took the name Gaozu, meaning High Founder or Progenitor, upon establishing the Tang Dynasty in 618.
Li Yuan (Gaozu) was born to father Li Bing, Duke Ren of Tang, and mother Duchess Dugu. Li Yuan inherited the title Duke of Tang when his father died in 572. When Northern Wei fell to the Sui dynasty in 582, Li Yuan retained this title, as he was nephew to the founding emperor’s wife.
In the early years of the Sui dynasty Li Yuan was a governor under first Emperor Wen, and later Emperor Yang (Li Yuan’s first cousin). During a period of upheaval in 613 Li Tuan became a military general in charge of operations in the region west of Tong Pass.
He declined to return when Emperor Yang recalled him that same year. During this time Li Yuan gained much military experience and support.
In 615 Li Yuan was in charge military operations in the Hedong area. In 616 he became a governor based in the vital city of Taiyuan. Here he continued to gather power and support. He also developed peaceful relations with the Gokturks, nomadic peoples dominating the important Silk Road trade.
Around this time the rule of the Sui dynasty was crumbling. Li Yuan began to plot a rebellion at the urging of his second son, Li Shimin. He strengthened his troops claiming it necessary due to threats from the Eastern Tujue. He disguised his efforts as a campaign to make Yang You, Emperor Yang’s grandson the emperor. With the help of several of his sons and daughters, Li Yuag was able to capture the capitol of Chang’an and established Yang You as Emperor Gong of Sui in late 617. Although many cities continued to recognize Emperor Yang, Li Yuan and his armies continued gradually defeating them.
The Tang Dynasty
Early in 618, Emperor Yang was killed by his general. Li Yuan convinced Emperor Gong to relinquish power. Li Yuan established the Tang Dynasty and became Emperor Gaozu on June 18th, 618. He was emperor during the first eight years of the Tang Dynasty. His sons were given royal titles and positions, including Li Shimin, named the Prince of Qin.
Emperor Gaozu worked to conquer other regions, thus unifying china under rule of the new Tang Dynasty. He restored many policies of the original Sui Emperor Wen, reversing several changes implemented by Emperor Wang. He also relaxed the harsh laws of the region and worked to promote trade.
Emperor Gaozu faced several military challenges early in the Tang Dynasty, the first of which came from Xue Ju, the leader of a neighboring small dynasty. Xue Ju fell ill and died early in the battle, and forces led by Li Shimin soon defeated his predecessor. Several more attempted uprisings were defeated by armies under Li Shimin, resulting in the incorporation of new regions into the Tang Dynasty.
In 1920, the Tang armies under Li Shimin began to invade the Zheng state. Wang, leader of Zheng, created an alliance with Dou, leader of the Xia state. Despite near victory of these combined forces, they were defeated by Tang forces in 1921. Zhenge territory and, briefly, Xia territory were incorporated into the Tang Dynasty. That same year Liang and Wu were defeated, and these regions also became part of the rapidly growing Tang Dynasty.
As the Tang Dynasty was beginning to thrive, rivalry was forming amongst Emperor Gaozu’s sons. Li Shimin had the best military records, and his forces led to defeat of the Tang Dynasty’s key rivals. This led him to have a superior military reputation, as well as the favor of his father, who considered naming Li Shimin crown prince. Meanwhile, Li Jiancheng made his own significant, if less impressive, contributions. Another son, Li Yuanji, supported Li Jiancheng and assisted in petitioning Emperor Gaozu to make him the crown prince instead.
In 622 Li Jiancheng led the battle against Liu Heita – the only remaining serious threat to the Tang Dynasty. The following year Liu was captured by one of his own officials. He was turned over to Li Jiancheng who executed him. Shortly thereafter, victory was declared. The goal of uniting China was nearly complete. By 624 however, Li Jianchenge began to bulk up his armies against Emperor Gaozu’s wishes and ignored his rulings. When the emperor learned of this, he put Li Jiancheng under arrest and promised to make Li Shimin crown prince. However, as soon as Li Shimin had left the city on a mission, supporters of Li Jiancheng, including Li Yuanji, successfully petitioned on his behalf. Emperor Gaozu released him and allowed him to remain crown prince.
End of Reign as Emperor
Throughout the reign of Emperor Gaozu economic and cultural development within the Tang Dynasty flourished – as did military power. The only remaining threat was frequent challenges from the Eastern Tujue, near the capitol city, Chang’an. However, by 626 the bitter rivalry between his sons was beginning to overshadow foreign threats.
When Li Shimin fell ill after eating at Li Jiancheng’s palace, both he and the emperor thought it was an assassination attempt. Both sons had loyal officials supporting their case with the Emperor while encouraging them to attack the other first.
The climax of the rivalry came when Emperor was set to send Li Shimin to lead the battle against yet another invasion by the Eastern Tujue. Li Jiancheng convinced the emperor to send Li Yuchi instead. Concerned by the idea that Li Jiancheng’s biggest supporter had a large army in his command, Li Shimin told his father that both Li Jiancheng and Li Yuchi were committing adultery, having relations with their father’s concubines. When Emperor Gaozu summoned the accused pair to return to the capitol, Li Shimin arranged an ambush to kill both of them on their way into the city.
After this brutal attack, Emperor Gaozu established Li Shimin as the crown prince. Only two months later, he released the throne making Li Shimin (who became Emperor Taizong) the Emperor of Tang.
Once retired, Emperor Gaozu had little control or influence on the policies of Tang. Despite relinquishing the throne in 626, he did not leave the main Taiji Palace until 629. At that time he moved to Hongyi Palace, and Emperor Taizong moved into the Taiji Palace. The following year Emperor Gaozu led the celebration when Emperor Taizong accomplished the long sought after victory over the Eastern Tujue. Emperor Gaozu fell ill in 634 and died in 635.