Song, known as Liu Song, Former Song (前宋) or Song of (the) Southern dynasties (南朝宋) in historiography, was an imperial dynasty of China and the first of the four Southern dynasties during the Northern and Southern dynasties period. It succeeded the Eastern Jin dynasty and preceded the Southern Qi dynasty.

The Northern and Southern dynasties was a period of political division in the history of China that lasted from 420 to 589, following the tumultuous era of the Sixteen Kingdoms and the Eastern Jin dynasty. It is sometimes considered as the latter part of a longer period known as the Six Dynasties (220–589). Albeit an age of civil war and political chaos, it was also a time of flourishing arts and culture, advancement in technology, and the spread of Mahayana Buddhism and Daoism. The period saw large-scale migration of the Han people to the lands south of the Yangtze. The period came to an end with the unification of all of China proper by Emperor Wen of the Sui dynasty.