When was the People's Republic of China founded?

The story behind the answer

October 1, 1949 is correct because Mao Zedong proclaimed the founding of the People’s Republic of China from Tiananmen in Beijing on that day, marking the Communist victory in the Chinese Civil War and the retreat of the Nationalist government (ROC) to Taiwan. It established Beijing as the capital and began sweeping political and social transformations across mainland China.

To remember it: 10/1 is China’s National Day—“first day of the tenth month for a new first start.” The other dates don’t fit: May 7, 1945 is around the end of WWII in Europe (VE Day is May 8); April 3, 1947 predates the Communist triumph; and December 6, 1950 is already into the Korean War.