On February 28, 1956, the Republic of Taiwan Provisional Government was established by Dr. Thomas Liao (a Taiwanese doctor in the United States) and others. It was one of the main overseas Taiwan independence movement organizations of its time.

Earlier, when the February 28 Incident occurred in Taiwan in 1947, Thomas Liao, his older brother Joshua Liao, and others facilitated the establishment of the Taiwan February 28 Massacre Joint Support Association in Shanghai, and issued a letter to people across the whole country. In the letter, they called for the removal of Taiwan Province Chief Executive Chen Yi, for people to be appointed to investigate the tragedy, and for the cancellation of monopolies on certain industries. The letter received no response. In June, the Liao brothers established the Formosan League for Re-emancipation and moved their base of operations to Hong Kong.

In 1949, Thomas Liao moved to Japan again. On February 28 of the following year, he held an event to mark the Third Anniversary of the February 28 Incident in Kyōtō. There, he made a statement advocating for Taiwan's independence, and was then arrested. In prison, Liao joined other Taiwanese people in Japan, along with Huang Nanpeng, Chen Zhemin, Lin Chunzhang, and others to reorganize the Formosan League for Re-emancipation. They established the Taiwan Democratic Independence Party in May of 1949.

In order to solidify the organization's representativeness and to stir up public discussion, on September 1, 1955, the Provisional Congress of Taiwan was formally established. On November 27th, the Provisional Congress of Taiwan passed the Organizational Pact for the Republic of Taiwan Provisional Government. According to this pact, the Provisional Congress of the Republic of Taiwan was then reorganized on January 15, 1956; Thomas Liao was elected President, Wu Zhennan as Vice President, and Guo Taicheng appointed to the role of Congressional Speaker. In 1956, on the ninth anniversary of the February 28 Incident, the Republic of Taiwan Provisional Government was officially established in Tōkyō, Japan. Many members were participants in Taiwanese politics, businesspeople, and students who had been exiled to Japan after the civil war. The Provisional Government demanded the realization of Taiwan's independence under the principle of national self-determination. On August 1 of 1956, the Provisional Constitution of the Republic of Taiwan was promulgated.

However, in the years that followed, the Provisional Government faced financial difficulties and internal divisions; the center of the Taiwanese independence movement overseas gradually shifted from Japan to the US. Coupled with internal struggles with the Taiwan Youth Association, the appeal of the Provisional Government deteriorated. In May 1965, as a result of the arrests of many of his family and friends, Thomas Liao returned to Taiwan to surrender to the government of the Republic of China. Between 1976 and 1977, successors Lin Taiyuan and Guo Taicheng also passed away. The Provisional Government announced its dissolution.

References: 吳三連台灣史料基金會 (Wu San-lien Foundation for Taiwan Historical Materials)(Chinese), 風傳媒 (Storm Media)(Chinese), 民報(Taiwan People News)(Chinese)