When was Taiwan formed?

In 1949 the CCP established the People's Republic of China as a Socialist State headed by a "Democratic Dictatorship" with the CCP as the only legal political party. The central government of the Chinese Nationalist Party was forced to retreat to the island of Taiwan that it had occupied at the end of World War II, and moved the ROC government there. Major armed hostilities ceased in 1950 but no peace treaty has been signed.