China, a History

Transition from Sui to Tang

Li Yuan (later to become Emperor Gaozu of Tang) was a former governor of Taiyuan when other government officials were fighting off bandit leaders in the collapse of the Sui Empire, with local elites developing defenses of their own. With prestige and military experience, he later rose in rebellion at the urging of his second son, the skilled and militant Li Shimin (later Emperor Taizong of Tang). Their family came from the background of the northwest military aristocracy prevalent during the reign of the Sui emperors. In fact, the mothers of both Emperor Yang of Sui and Gaozu of Tang were sisters, making these two emperors of different dynasties first cousins.

Li Yuan installed a puppet child emperor of the Sui Dynasty in 617 but he eventually removed the child emperor and established the Tang Dynasty in 618. Li Yuan ruled until 626 before being forcefully deposed by his son Li Shimin, Prince of Qin, known as "Tang Taizong." Li Shimin had commanded troops since the age of 18, had prowess with a bow, sword, lance, and was known for his effective cavalry charges. Fighting a numerically superior army, he defeated Dou Jiande at Luoyang in the Battle of Hulao in 621. In a violent elimination of royal family due to fear of assassination, Li Shimin ambushed and killed two of his brothers, Li Yuanji and Crown Prince Li Jiancheng in the Incident at Xuanwu Gate on July 2, 626. Shortly after, his father abdicated in favor of him and he ascended the throne as Emperor Taizong. Although his rise to power was brutal and violent, he showed to be a capable leader who listened to the advise of the wisest members of his council. In 628, Emperor Taizong held a Buddhist memorial service for the casualties of war, and in 629 had Buddhist monasteries erected at the sites of major battles so that monks could pray for the fallen on both sides of the fight. This was during Emperor Taizong's campaign against Eastern Tujue, a Göktürk khanate that was destroyed after the capture of Jiali Khan Ashini Duobi by the famed Tang military officer Li Jing (571–649), who later became a Chancellor of the Tang Dynasty.