The southward expansion of the Han dynasty comprises a series of military campaigns and expeditions in what is now modern southern China and northern Vietnam.

Military expansion to the south began under the previous Qin dynasty and continue during the Han.

Campaigns are dispatched against the Yue tribes, leading to the annexation of Minyue by the Han in 135 BCE and 111 BCE, Nanyue in 111 BCE, and Dian in 109 BCE.Chinese culture influences the newly conquered territories, and merges with native traditions.

Han influences are apparent in artifacts excavated in the Baiyue tombs of southern China.

This influence extends to the kingdoms of Southeast Asia, where contact leads to trade and diplomacy.

The demand for Chinese silk establishes trade routes between Europe, the Middle East, and China.