In 1894 China and Japan went to war over their conflicting interests in Korea. Japan won the conflict handily. The Treaty of Shimonoseki (1895), which ended the war, contained a provision that ceded Taiwan and the P’eng-hu Islands to Japan in perpetuity. The Western powers regarded the treaty as legally binding, but China did not, seeing it as an agreement imposed on it under duress.

When news of the treaty reached Taiwan, local leaders there proclaimed the Republic of Taiwan—Asia’s first republic—but its life was brief, lasting only about 10 days. Taiwan had no central government, was plagued by warlordism (causing many residents of the island to feel that Japanese rule would be an improvement), and had neither a recognized leader nor a real military. Moreover, Japan was determined to make Taiwan a colony, so it dealt firmly with opposing movements on the island.

Japan’s military at first governed the island, but within three years those forces were seen as being no longer necessary. Taiwan, Tokyo’s first attempt at colonialism, was an experiment with which Japan had great success in establishing order, eradicating disease, building infrastructure, and creating a modern economy. Taiwan soon became the most-advanced place in East Asia outside Japan itself.

Japan’s policy makers focused on agriculture first and improved rice production with new seeds and farming techniques. Rice and sugar were exported. Taiwan had about 30 miles (50 km) of railroads when Japan took control of the island, but within a decade it had increased the track length to some 300 miles (500 km), and much more construction was planned. Taiwan was soon electrified, which facilitated the growth of new industries such as textiles and chemicals. World War I was a boon for Taiwan’s economy, as new industries were developed and trade expanded. World War II also had a positive impact on the island’s economy.

On the other hand, Japan ruled Taiwan strictly, using harsh punishment to enforce the law. Tokyo, initially at least, showed no interest in making Taiwan a democracy. Moreover, in governing Taiwan, Japan experienced a dilemma over whether to make the colony part of Japan or to allow it to be administratively separate and to some degree self-governing. Ultimately, Tokyo resisted assimilating Taiwan, although it did force the population there to learn Japanese and absorb Japanese culture. That strategy had advantages for the people of Taiwan, as it gained for them access to science and technology, but such advantages came at the cost of suppressing local culture and the Chinese language.

In 1935, after Lin Hsien-t’ang (Lin Xiantang) of Taiwan’s Home Rule Association advocated the transfer of more political power to local officials, Japan announced the establishment of a somewhat autonomous local government. An election was held, and there was some evidence for the beginnings of democratic government in Taiwan. That movement was short-lived, however, as the militarists in Japan rose in power there the following year.

In 1937, after Japan invaded China and touched off the second Sino-Japanese War, Taiwanese (Chinese inhabitants of Taiwan) were given the option of moving back to China, though few did. In the period before the war in the Pacific widened to include the United States and its allies in 1941, Japan came to regard Taiwan as an “unsinkable aircraft carrier” and an important stepping-stone in its military expansion. Japan established military bases there and used them as staging areas for invasions of the Philippines and other areas to the south.

The Taiwanese worked in Japan’s defense and war-related industries in Taiwan and in other ways abetted Japan’s war efforts. Many Taiwanese served in the Japanese military, including units that fought in China. Taiwanese troops even participated in the atrocities against Chinese civilians at Nanjing (Nanking) and other places on the mainland. Of the Taiwanese who served in the Japanese military, more than 30,000 were killed in combat.

During the last months of the war, Allied military strategists discussed a plan to invade Taiwan. They abandoned the plan, however, when they discovered that the U.S. military had few good maps of the island and after they concluded that the Taiwanese would fight alongside Japanese troops. U.S. warplanes bombed oil-storage depots and some other strategic targets in Taiwan, but little damage was done to the island otherwise.

Earlier, in a declaration issued after the first Cairo Conference (1943), the United States and Britain concurred with Chinese Nationalist leader Chiang Kai-shek that Taiwan was territory Japan had taken from China and therefore would be returned to China. That decision was confirmed at the Potsdam Conference (July–August 1945). Hence, U.S. forces present in Taiwan in 1945 to accept the Japanese surrender there turned over control of the island to Chiang. However, an official or legal dispensation regarding Taiwan awaited a peace treaty.

Taiwan’s Chinese population welcomed the end of Japanese rule and the restoration of the island to Chinese control, but they were also apprehensive. The communist forces of Mao Zedong that were at war with Chiang’s Nationalist armies in China had almost no contact with Taiwan. The American public wanted its troops to come home, and the U.S. government was focused more on problems in Europe than on those in Asia.