The so-called "Six Dynasties" refers to: (1) Three Kingdoms Wu. Sun Quan is the king, and the capital is Jianye (now Nanjing). (2) Eastern Jin Dynasty. In 3 17, Si Marui, a royal family of the Western Jin Dynasty who fled to the south of the Yangtze River, proclaimed himself emperor in Jiankang (now Nanjing) and established the Eastern Jin regime. (3) During the Northern and Southern Dynasties, the four dynasties of Song, Qi, Liang and Chen all made Jiankang (now Nanjing) their capital. Therefore, Nanjing is called "the ancient capital of the Six Dynasties" in history. As for the Ming Taizu Zhu Yuanzhang, whose capital is Yingtian (now Nanjing), and the Taiping Heavenly Kingdom, whose capital is Tianjing (now Nanjing). They were not included in the Six Dynasties. There are only three dynasties with Beijing as their capital in history: (1) Yuan Dynasty. In A.D. 127 1 year, Kublai Khan made the country Yuan and the capital Dadu (now Beijing) the following year. (2) Ming dynasty. After Ming Taizu Judy ascended the throne, in order to strengthen the military defense forces in the north, Beijing was built in 14 17, which took more than three years to complete, and 142 1 moved its capital to Beijing. (3) Qing dynasty. In 1644, the Ming dynasty was overthrown by the peasant army. After the Qing army entered the customs, the Qing dynasty began to rule the whole country and then moved its capital to Beijing.