When did the Korean nationality in Northeast China migrate to Northeast China?

The ancestors of Korean people in China are Koreans who moved from the Korean Peninsula to the three northeastern provinces of China. After they settled down, they gradually developed into a nation in China. 1982 during the national census, it was found that some Korean ancestors in China had settled in the northeast as early as the late Ming and early Qing dynasties. For example, Han surnamed Park in Pujiagou Village, Gai County, Liaoning Province, has settled in the local area for more than 300 years. Since the middle of19th century, more and more Koreans have moved in from the Korean peninsula, which is the main source of Koreans in China. Due to the cruel exploitation and oppression of the feudal ruling class in Korea at that time, especially in 1869, the northern part of Korea suffered a great disaster. Some suffering Korean farmers crossed the Yalu River and Tumen River and came to China to reclaim land along the two rivers, where they lived with the Han and Manchu people. But at this time, the number of people moving in is not very large, most of them come in spring and go in autumn, and their residence is still unstable. With the intensification of Japanese imperialist aggression against Korea, a large number of residents moved to the northeast frontier of China in order to find a way out, regardless of the ban of the Qing government. According to statistics, in 1870, there were 28 Korean-inhabited towns on the north bank of Yalu River. In the seventh year of Guangxu in Qing Dynasty (188 1), there were more than 10000 Koreans in Yanbian area. From 65438 to 0883, there were more than 37000 Korean residents in Ji 'an, Linjiang and Xinbin counties. During the same period, a large number of Korean farmers moved into the areas along the Wusuli River. 19 In the 1950s and 1960s, the Qing government still adopted the policy of prohibiting North Korean farmers from entering the country. Later, the policy of recruiting people to fill the sea was changed. 188 1 year, set up famine relief bureau in Jilin and reclamation bureau in Nangang (Hunchun), Yanji and Donggou to recruit immigrants. All the recruits are from China. 1885, the Qing government designated the northern bank of Tumen River, which is about 700 miles long and 50 miles wide, as a special reclamation area for Korean farmers, so as to facilitate a large number of Korean farmers to move to the northeast. 19 10, Japanese imperialism annexed Korea, and the Korean people and some patriots moved to the northeast of China in large numbers, which reached more than 360,000 in 19 18.