Just I came up with a old news related with China government. It was quite seriously dealt in Korea mess media in 2006. The Chinese name is 東北邊疆歷史與現狀系列硏究工程. This is a China government official project.
China government now insists that long time ago North Korea region belonged to China. Briefly saying, it is a kind of distorting history, like Japan distorts their own history about World War Second. Many people proposes different interpretation about it. I summarize them here briefly.
In short-term, the project justifies that China combines many different minority tribes around northern part of North Korea. They want to alleviate high tense among minorities, enforcing nationalism.
In long-term, it is basic work to prepare a certain situation that could happen in North Korea. It is already well-known facts that Japan and China are all highly interested in North Korea for their own benefits. Changing history, China can insist any kind of right of benefit from North Korea.
Although I don't care about this kind of nationalism fighting, most of Korean were very angry about that. And our president had also announced.