evidence: The People's Republic of China was founded in 1949 after the Communist Party defeated the nationalist Kuomintang, who retreated to Taiwan, creating two rival Chinese states - the People's Republic on the mainland and the Republic of China on Taiwan. [...] PEOPLE'S REPUBLIC OF CHINA: FACTS [...] 1945-49 - China's civil war resumes as Japan's military defeat becomes clearer. The Communists gain control of mainland China and established the People's Republic of China in 1949 under Mao Zedong, forcing the leadership of the Republic of China to retreat to the island of Taiwan.