Do we Koreans have anything to do with the two nationalities on the Korean Peninsula?

Korean is a descendant of Chiyou and a branch of Jiuli nationality. Yan Di and the Yellow Emperor defeated Chiyou together and established the political power along the Yellow River. After the defeat of the Jiuli nationality, some fled to the south, some joined the Yanhuang nationality, and some became the present Korean nationality. The Koguryo dynasty ruled a part of the land in the northeast of China, and the Korean dynasty also ruled a part of the land in the northeast of China. However, due to the repeated attacks in the Sui and Tang Dynasties, a lot of land was lost. After the collapse of the Koryo Dynasty, osawa Rong established the Bohai Kingdom in the northeast of China. In order not to be ruled by Silla slaves, a large number of Koreans migrated to the northeast of China and the northwest of China-Uzbek generation. Korean people in China moved to northeast China in large numbers in the late Qing Dynasty. After the Japanese colonized the Korean peninsula, many Koreans fled to the northeast of China to survive. After the Japanese colonized the northeast of China, Manchukuo was established. Although there is a dividing line between Manchukuo and Koreans on the Korean peninsula, they can travel freely. After Japan surrendered, the Kuomintang government implemented the Japanese colonial treaty: Koreans living in China were not allowed to merge with the Korean Peninsula. Since China, Koreans have been divided into two parts. During the War of Resistance against Japanese Aggression period, many Koreans were captured in Japan, and many fled to Europe and America. After the end of War of Resistance against Japanese Aggression, the two forces on the Korean peninsula did not give way to each other, and the Democratic People's Republic of Korea was established in the north. The Republic of Korea was founded in the south. Since then, the nation has been divided into many branches. Although they are the same nation, with the same written language and customs, their cultural differences are widening and contradictions are worsening. South Korea and North Korea will be reunified one day, but the Koreans in China will always be members of the Chinese nation.