From about 1927 to 1950 resulting in two nations; China (PRC - People's Republic of China - Mao Tse Tung) and Taiwan (Republic of China - which had a governor).
The People's Republic of China (China) was not recognized for some time by the USA due to it's loyalty to Taiwan. Taiwan didn't trust the USA and didn't want to be a territory of the USA. The relationship continues today.
The USA attempted to block PRC from becoming a member of the United Nations. It didn't work and now they are permanent nuclear nation. The tensions between China and the USA continued until the 1970s. I think the tensions were mostly imagined by the USA to allow it's support of Taiwan.
Taiwan is south of Japan and north of the Philippines. I just thought I'd point that out. Today the USA has a "One China Policy."
