International recognition of Taiwan

Following the ROC central government’s retreat since 1949, the effective territories of the Republic of China (ROC) has been limited to Taiwan and its associated islands, and lost control of mainland China due to its defeat in the Chinese Civil War by the Chinese Communist Party (CCP), which established the People's Republic of China (PRC) that same year. The division marked the start of cross-strait relations and the emergence of two rival governments on opposite sides of the Taiwan Strait, each claiming to be the sole legitimate authority over both the Chinese mainland and Taiwan.

Source: Wikipedia — International recognition of Taiwan (CC BY-SA 4.0)