Do Ryukyu Islands belong to China?

Obviously, it belongs to China. During the Three Kingdoms period, people from Wu immigrated there.

The Eastern Jin Dynasty, the Southern Dynasties, the Sui and Tang Dynasties, and the Fujian and Vietnam all recorded the documents about immigrants to Ryukyu.

The Song Dynasty formally brought Ryukyu under its jurisdiction.

Yuan, Ming, Nan Ming (Zheng's) and Qing Dynasty all had jurisdiction over Ryukyu Islands.

After the victory of the Anti-Japanese War in the Republic of China, Ryukyu, as an affiliated island, should be returned to China together with Penghu Islands.

Due to the behind-the-scenes manipulation of the United States and the Soviet Union, Ryukyu did not return to the embrace of the motherland.