explain one example of how the xiongnu influenced han policy
Han–Xiongnu War By the reign of Emperor Wu, the Han empire was prospering and the national treasury had accumulated large surpluses.[16] However, burdened by the frequent Xiongnu raids at the frontier of the Han empire, the emperor abandoned the policies of his predecessors to maintain peace with the Xiongnu early in his reign.[17] In 136 BC, after continued Xiongnu incursions near the northern frontier, Emperor Wu had a court conference assembled.[18][19] The faction supporting war against the Xiongnu was able to sway the majority opinion by making a compromise for those worried about stretching financial resources on an indefinite campaign: in an engagement along the border near Mayi, Han forces would lure Junchen Chanyu over with wealth and promises of defections in order to eliminate him and cause political chaos for the Xiongnu.[18][19] Emperor Wu launched his military campaigns against the Xiongnu in 133 BC.[20][21]
Chinese domination of Vietnam The Chinese domination of Vietnam (Vietnamese: Bắc thuộc, Hán tự: 北屬, "Belonging to the North (China)"[1][2][3]) began in 111 BC, and is usually considered to have ended in 938 AD. A fourth, relatively brief, 20-year punitive invasion by the Ming dynasty, 400 years later, is usually excluded by historians in discussion of the main, almost continuous, period of Chinese colonization from 111 BC to 938 AD, as is the brief occupation of northern Vietnam by Chinese forces at the end of the Second World War.