The relationship between Han Dynasty and Xiongnu (1) The first stage: the pro-Xiongnu policy was adopted in the early Western Han Dynasty. Reason: The Huns were very strong, but the Western Han Dynasty experienced the peasant war at the end of Qin Dynasty and the Chu-Han war, and the economy was depressed and the national strength was weak. Impact: It helps to concentrate on restoring the economy and enhancing national strength. (2) The second stage: Emperor Wu of the Han Dynasty launched three large-scale wars against the Huns. Reason: After the recuperation in the early Han Dynasty, by the time of Emperor Wu of the Han Dynasty, the economy was prosperous, the national strength was strong, and it had the power to defeat the Xiongnu. Influence: It won a decisive victory, basically relieved the threat of Xiongnu to the northern border counties, and was conducive to the development of the border areas. (3) The third stage: At the end of the Western Han Dynasty, the policy of affinity was implemented, and the Emperor of the Han and Yuan Dynasties took Wang Zhaojun as his concubine and married Uhaanyehe far away. Reason: Civil strife in Xiongnu, the problem of capital city in the late Western Han Dynasty was serious, and it was unable to launch a large-scale war. Influence: After years of war between China and Hungary, the two sides have prospered, cultural exchanges have increased, and they have lived in harmony, which has strengthened the relations between China and Hungary. Promote the social and cultural development and ethnic integration of the Huns. (After Zhaojun left the fortress as a messenger of peace, there was no war between the Han Dynasty and the Xiongnu for about 50 years, and there was a peaceful scene in the border areas, in which "No warning from dogs and barking dogs, no war in Li Shu, a prosperous population and overwhelming cattle and horses". (4) In the early Eastern Han Dynasty, the Xiongnu split, the southern Xiongnu moved inward, and the northern Xiongnu lived in the Mongolian plateau, harassing the south and controlling all ethnic groups in the western regions. The government of the Eastern Han Dynasty defeated the Xiongnu twice with Dou Gu and Dou Xian, and finally relieved the Xiongnu's threat to the Eastern Han Dynasty and the Western Regions.