What happened
Defeated in the Chinese Civil War, Chiang Kai-shek's Nationalist government withdraws to Taiwan with its remaining forces, gold reserves and its claim to be the legitimate government of all China. The Communist victory establishes the People's Republic in Beijing in October. Two governments now claim to be China; neither concedes.
This is the origin of the dispute in its modern form — and its essential character. The Taiwan question is the unfinished end of a civil war, not an invasion of one state by another, which is why the legal arguments are so intractable and why "restoring the status quo" means different things to every party.
Confidence: High
See this event in the timeline Interactive: select this record and follow what connects to it.