Which countries originated from China or China and migrated or split? List them one by one, preferably with examples.

After the demise of Shang Dynasty, Korea and South Korea, which originated from Jizi Korea, were recognized by Zhou Wuwang. As a dependent country of China.

Mongolian, the Republic of China, became independent after the victory of the Anti-Japanese War, and was originally China Outer Mongolia.

Kyrgyzstan is a Central Asian country, mostly located in the Pamirs. The former Pamirs belonged to China, but it was only after modern times that it split. Today, China occupies only a small part of the plateau.

Vietnam, once called China, was once a vassal state of China. In the late Qing Dynasty, it became independent from the suzerain country China and was colonized by the French for a long time.

In Singapore, more than 70% are Chinese.