What is the relationship between Korea and Ming Dynasty?

During the Ming Dynasty, China was the suzerain of North Korea. There were not only political and economic exchanges, but also a war to resist Japan and aid Korea, which was won. The Ming Dynasty's aid to War of Resistance against Japanese Aggression was a war between Chinese and Korean people against Japanese aggression during the Wanli period of the Ming Dynasty. From 1592 to 1598. 1592 is the year of Renchen, so Korean historians call the war of 1592- 1598 the war of Renchen defending the country. In the Ming Dynasty, China and North Korea always got along well, and envoys exchanged frequently. At that time, China exported silk, cloth, medicinal materials and other items to North Korea, and especially allowed North Korea to buy nitrate yellow, gunpowder, ox horn and so on, which were forbidden to be sold in the Ming Dynasty. North Korea exports cattle, horses, paper and ramie cloth to China. Political friendship and economic mutual assistance have promoted cultural exchanges between the two countries. The relationship between North Korea and China at that time can be seen.