For almost as long as it existed, Taiwan had strong influence and interaction with China that shaped it into what it is today. From as early as the seventh century CE, the Chinese people have been migrating in large numbers from the Chinese mainland to the neighboring island of Taiwan (GALE, 1). After some time, China had gained control of the island in 1683 and eventually made it an official province of the mainland Chinese government in 1885 (GALE, 1).
Shortly after, in 1895, Japan took control of Taiwan as a result of the Sino-Japanese and it belonged to Japan for the next 50 years as a colony (GALE, 1).
In 1945, during the Japanese surrender of World War II, the opposing Chinese force reclaimed the island Taiwan. At around the same time, a civil war erupted in China between the nationalist Kuomintang and the Chinese communist forces. Four years later, in 1949, the Chinese nationalists were defeated, and then fled to Taiwan where it would reestablish its government months later, while the communist forces established the new People's Republic of China in Beijing (BBC, 2).
Map Showing Territories controlled by the PRC and the ROC (wikipedia.com)
As a result of the divide, both the People's Republic of China and the Republic of China believed that they represented all of China (BBC, 3). Although this confusion created tensions between the two governments, both sides had the common belief that all of China, including both the mainland and the island of Taiwan, belong to a single nation, known as the “One China Policy” (Edelman, 1). This is a proposition that states that China is a single nation ruled by one government. But with both governments making claims of ownership of China, there is confusion about who it belongs to. However, since their divide, the People's Republic of China has threatened to use force if Taiwan ever formally declares its independence (GALE, 1). And in 1971, the United Nations officially recognized the People's Republic of China as the sole government of China, replacing the Republic of China’s membership (Edelman, 2). Today, it is almost universally accepted that China, including Taiwan, is part of the People's Republic of China as well as the fact that the Republic of China is not recognized as an independent nation with the exception of 22 countries.