The birthplace of ancient civilization and the spread of cultural civilization in the Central Plains.

The birthplace of Chinese civilization is in the Central Plains, that is, the middle reaches of the Yellow River and now Henan. This area is located in the infiltration center of the east, west, north and south, which makes it superior to other areas in adsorption and diffusion. The Central Plains is also the most concentrated area of wars and disasters in the history of China. Many nationalities, races and regimes compete for control of the Central Plains. In different historical periods, a large number of Zhongyuan people moved to foreign countries in order to escape the war, which greatly promoted the development of many places and the spread of Chinese civilization.

This outward expansion is the Central Plains in a broad sense, which is directly adjacent to the source of Chinese civilization. With the expansion of China culture from the source to the periphery, after the Qin and Han Dynasties, the cultural circle in China gradually became clear and stereotyped. In the early days, the culture of the Central Plains spread smoothly to the north and the west, and then it was further brought into the cultural circle of China through the dynasties established by two ethnic minorities-the Yuan Dynasty and the Qing Dynasty.

The spread of Central Plains culture to the south met with stubborn resistance in the early days, such as the fiasco of King Zhao Zhou attacking Chu, which showed the defeat of Zhou Wenhua's spread to the south. However, after the end of the Eastern Han Dynasty, the war in the north caused the Central Plains immigrants to move southward again and again, which made the source civilization spread southward to the Yangtze River basin, southwest, Lingnan, Fujian, Taiwan Province and other places with the population migration. Han culture also spread to some of China's close neighbors, North Korea and Japan in the northeast, Mongolia in the north, Central Asia in the west and Southeast Asian countries in the south. These places constitute the outer edge of China's cultural circle.

The radiation of Central Plains culture to the outer edge of Central Plains cultural circle is also related to immigration. For example, when China culture influenced Korea and Japan, it involved the legendary Kiko and Xu Fu, and then a large number of immigrants from the Korean Peninsula and Shandong Peninsula moved overseas continuously, making Chinese civilization extend to every corner of the world. From the process of cultural circle expansion in China, it is not difficult to draw a conclusion that immigrants have an important influence on cultural exchange, cultural diffusion and cultural communication. Because of the war, there were three waves of immigrants from the Central Plains in history.

1 After the Yongjia Rebellion, some refugees from Hebei, Shandong, Shanxi, Henan, Jiangsu, Anhui and other provinces have crossed the Huaihe River and headed south one after another. According to today's division, Jiangsu Province is the region that receives the most immigrants, with the most concentrated in Nanjing, Zhenjiang and Changzhou, while Yangzhou and Huaiyin are the main places in northern Jiangsu.

2. The Anshi Rebellion led to the second southward migration of a large number of people in the Central Plains. "The world is dressed in clothes, avoiding Wu Dong, and Yongjia moving south is not here." East Road enters Huainan and Jiangnan from the North China Plain, and then mainly enters Jiangxi through Jinqu Basin in southern Anhui and western Zhejiang. Divided into two, one south to Lingnan; One crossed Wuyishan and entered Fujian. West Road enters the present Nanyang and Xiangyang areas from Guanzhong and the western part of North China Plain, then goes south, passes through southern Hubei and Hunan, and enters Lingnan. The southward migration lasted for a century and a half until the early years of the Northern Song Dynasty, and the number of people could not be verified. After the "An Shi Rebellion", the people of the Central Plains moved south, and the population ratio between the north and the south was balanced for the first time.