The second emperor of the Tang dynasty of China. Li Shimin was the second emperor of the Tang dynasty of China, ruling from 626 to 649. He is traditionally regarded as a co-founder of the dynasty for his role in encouraging Li Yuan, his father, to rebel against the Sui dynasty at Jinyang in 617. Taizong subsequently played a pivotal role in defeating several of the dynasty's most dangerous opponents and solidifying its rule over China. Taizong is typically considered to be one of the greatest emperors in China's history and henceforth, his reign became regarded as the exemplary model against which all future emperors were measured. His era, the "Reign of Zhenguan" is considered a golden age in Chinese history!