The Democratic Progressive Party was established under the martial law in Taiwan, becomes the first opposition party in Taiwan.

Martial law in Taiwan (Chinese: ; pinyin: Jiyn Shq; Peh-e-j: Ki-gim s-k) refers to the periods in the history of Taiwan after World War II during control by the Republic of China Armed Forces of the Kuomintang-led Government of the Republic of China regime. The term is specifically used to refer to the over 38-year-long consecutive martial law period between 20 May 1949 and 14 July 1987, which was qualified as "the longest imposition of martial law by a regime anywhere in the world" at that time (having since been surpassed by Syria.).

With the outbreak of Chinese Civil War, the Declaration of Martial Law in Taiwan Province (Chinese: ; pinyin: Tiwn Shng Jiyn Lng; Peh-e-j: Ti-on-sng Ki-gim Lng) was enacted by Chen Cheng, who served as the chairman of Taiwan Provincial Government and commander of Taiwan Garrison Command, on 19 May 1949. This order was effective within the territory of Taiwan Province (including Island of Taiwan and Penghu). The provincial martial law order was then superseded by an amendment of the Declaration of Nationwide Martial Law which was enacted by the central Government of the Republic of China after the amendment received a retroactive consent by the Legislative Yuan on 14 March 1950. Martial law in Taiwan Area (including Island of Taiwan, Penghu) was lifted by a Presidential order promulgated by President Chiang Ching-kuo on 15 July 1987.

The Democratic Progressive Party (DPP) is a Taiwanese nationalist and center-left political party in Taiwan (Republic of China). Controlling both the Republic of China presidency and the unicameral Legislative Yuan, it is the majority ruling party and the dominant party in the Pan-Green Coalition as of 2022.

Founded in 1986, the DPP is one of two major parties in Taiwan, along with the historically dominant Kuomintang. It has traditionally been associated with strong advocacy of human rights, and a distinct Taiwanese identity. The incumbent President and three-time leader of the DPP, Tsai Ing-wen, is the second member of the DPP to hold the office.The DPP is a longtime member of Liberal International and a founding member of the Council of Asian Liberals and Democrats. It represented Taiwan in the Unrepresented Nations and Peoples Organization. The DPP and its affiliated parties are widely classified as socially liberal because of their strong support for human rights, including support for same-sex marriage and other LGBT rights. They are also proponents of a Taiwanese national identity. In addition, the DPP is more willing to increase military expenditures to defend against a potential Chinese invasion, and on foreign policy favors closer ties with the United States and Japan.