The policy of Qing dynasty to North Korea in the two decades at the end of the 19th century

In 1879, after the merger of Ryukyu, Japan directly threatened North Korean security and the bilateral relationship between the Qing and North Koreans. At this time, the great powers like America, Britain, France, Germany ... also want to open the door of trade with North Korea. In order to maintain the traditional order of suzerain-vassal relationship and ensure border security, the Qing Dynasty implemented a policy of active engagement, which had a great influence on the political landscape of Northeast Asia at that time.