Taiwan is an East Asian nation. It borders the People's Republic of China (PRC) to the northwest, Japan to the northeast, and the Philippines to the south on the sea. Taiwan's main island, formerly known as Formosa, covers 35,808 square kilometers, with mountain ranges dominating the eastern two-thirds and plains dominating the western third, where the island's densely populated populace is centered. The capital is Taipei, which, together with New Taipei City and Keelung, comprises Taiwan's biggest metropolitan region. Kaohsiung, Taichung, Tainan, and Taoyuan are also important cities. Taiwan, with a population of 23.45 million people, is one of the world's most densely inhabited countries.

Taiwanese indigenous peoples' Austronesian-speaking ancestors settled the island some 6,000 years ago. Large-scale Han Chinese settlement to western Taiwan began in the 17th century as a Dutch colony and continued under the Kingdom of Tungning. The Chinese Qing dynasty seized the island in 1683 and relinquished it to the Japanese Empire in 1895. Following Japan's surrender in 1945, the Republic of China, which had ousted the Qing in 1911, acquired control of Taiwan on behalf of the World War II Allies. The restart of the Chinese Civil War ended in the ROC's fall of mainland China to Chinese Communist Party forces in 1949, and its retreat to Taiwan. Since then, its effective authority has been restricted to Taiwan and a few smaller islands.