Flag of the Republic of China sovereign independent country of the Republic of China (ROC) to the island of Taiwan. On the mainland, the communist forces of Mao Zedong established the People's Republic of China and adopted their own national flag. On October 23, 1954, the National Emblem and National Flag of the Republic of China Act () was promulgated by the Legislative Yuan to specify the size, measure, ratio, production, and management of the flag. While public display of the ROC flag is generally frowned upon, and may even lead to arrest in the PRC, Cambodia was the first country to outlaw it officially. In
History of the Republic of China operations of 1950 were more successful: they led to the Communist conquest of Hainan Island in April 1950, capture of Wanshan Islands off the Guangdong coast (May–August 1950) and of Zhoushan Island off Zhejiang (May 1950). In June 1949 the ROC declared a "closure" of all mainland China ports and its navy attempted to intercept all foreign ships. The closure covered from a point north of the mouth of the Min River in Fujian province to the mouth of the Liao River in Manchuria. Since mainland China's railroad network was underdeveloped, north-south trade depended heavily on sea lanes. ROC naval