Immigrants moved south in the late Western Han Dynasty.

After the establishment of the Han regime, due to various reasons, immigration activities of different scales were carried out, mainly in Guanzhong area and northwest frontier areas. Among them, it is mainly to increase the population of Guanzhong and increase the resistance to Xiongnu, and kanto region immigrated to Guanzhong; Moving to the northwest is to strengthen border defense and solve the problem of land shortage for refugees in Neixian County.

Immigration in Hetao area of Inner Mongolia and Hexi Corridor of Gansu Province is compulsory. At the same time, the Western Han government also followed the measures of migrating dignitaries in the Qin Dynasty. From the beginning of the Western Han Dynasty to the beginning of the Han Dynasty, a large number of officials moved to Sanfu for more than 100 years. By the end of the Western Han Dynasty, immigrants and their descendants had accounted for more than half of the local population. After Emperor Wu of the Han Dynasty, this area became one of the most densely populated and economically and culturally developed areas in China. During the Western Han Dynasty, the population distribution in kanto region was the densest, mainly concentrated in the middle and lower reaches of the Yellow River and north of Huaishui.

That is, east of Taihang Mountain, south of Yanshan Mountain and north of Huaishui to the coastal area, that is, the North China Plain. The area of this area is less than 15% of the whole country, but the population accounts for more than 60%. The unique immigrant culture-the frequent and numerous migration of ethnic minorities in Han Dynasty was closely related to the social and economic situation at that time. After 50 or 60 years of rest and recuperation, the people's lives have been stable, the social economy has developed, and the country has gradually become rich and strong. At this time, Emperor Wu of the Han Dynasty defeated the Xiongnu in the north, made 36 countries in the Western Regions descend to the west, and wiped out the Zhao regime in South Vietnam.

Move the Huns to Sene. According to Hanshu, in the autumn of the second year of Yuanshou, "Xiongnu evil Wang Kun killed Xiutu Wang, gathered more than 40,000 people to surrender him, and placed him in the position of five vassals. Take its land as Wuwei and Jiuquan County ". In the winter of the first year of Wufeng in Xuan Di, the Xiongnu Warrior Khan led more than 50,000 people to surrender and was placed in Xihe and Beidi. According to Mr. Ge's statistics, the Huns who moved in the Yuan Dynasty within two years may be close to 200,000. During the Eastern Han Dynasty, Xiongnu was divided into north and south parts. In 49 A.D., Nandan became a vassal, led his troops to the Han Dynasty, and later settled in Wuyuan, Shuofang, Dingxiang, Yanmen and other counties. They lived with the Han people and gradually absorbed the Han culture and production technology.

Coupled with the stable living environment, many northern Huns have also returned to Han. According to "Biography of Southern Xiongnu in the Later Han Dynasty", when Emperor Wudi of the Eastern Han Dynasty was in power, the Northern Xiongnu guarded the hills and led thousands of people to surrender. During the reign of Emperor Gaozu Zhang, Zeng Daren of Sanmulou of the Northern Xiongnu sent more than 30,000 people to Han. During the Northern Dynasty chaos, there were 58 departments, including Qulan, Chubei and Hudu, with more than 200,000 people, who went to Yunyun, Wuyuan, Shuofang and Beidi. During the Han Dynasty and the Emperor, troops were sent out of Shuofang to attack the northern Xiongnu and captured more than 200,000 people. In 1978 alone, more than 400,000 northern Huns moved in, and the number was indeed considerable.