In the
Ming dynasty, Yanbian was governed by the Jianzhou Guard () and in the late
Qing dynasty the area was divided into the Yanji () and Hunchun ()
subprefectures. From 1644 to 1800s, the Manchurian Qing state maintained a policy of disallowing Han Chinese immigration into traditionally Manchurian lands in order to ensure that the Manchu were not assimilated by the Han Chinese. However, this effort failed because of the trading and agricultural opportunities available to Han Chinese migrants in the northeast region which made it profitable to evade the rules, as well as later Qing relaxation of the same rules (
Chuang Guandong) to discourage
Russian encroachment. Thus, in the 19th century, Chinese immigrants migrated en masse from China proper to areas that were formerly off limits to Han Chinese migration. In the late 19th century, Korean immigrants migrated en masse from the
Korean Peninsula to China. Korean (
Joseon) migration into
Northeast China began in significant numbers in the last quarter of the 19th century and was mainly motivated by economic hardship on the Korean side of the border. After the Japanese annexed Korea in 1910, a small but significant number of migrants also came to Manchuria for political reasons. After the foundation of the
Republic of China, a second wave arrived. Of the 2 million ethnic Koreans in Manchuria at the time of the communist takeover, 1.2 million remained in the region after the end of
World War II. Many participated in the
Chinese Civil War, most on the side of the Chinese communists. On the 3rd of September 1952, the Yanbian Autonomous Region was established. This was the sixth of over 157 different administrative areas created in the 1950s for ethnic minorities in China. In December 1955, Yanbian was 'administratively downgraded' to an Autonomous Prefecture due to its 'insufficiently large' population. During the
Cultural Revolution, ethnic Koreans were killed and persecuted in Yanbian. Many non-Han Chinese residents of Yanbian were suspected to be disloyal to the Chinese state, and subsequently beaten, killed, publicly humiliated, fired, exiled or imprisoned. From the late 1990s, the
Chaoxianzu have assimilated into mainstream Chinese culture with increasing speed, often switching to daily use of Chinese and choosing to attend Chinese-language schools. ==Geography==