Lying off the southeastern coast of the China mainland, Taiwan is China's largest island and forms an integral whole with the mainland.

Taiwan has belonged to China since ancient times. It was known as Yizhou or Liuqiu in antiquities. Many historical records and annals documented the development of Taiwan by the Chinese people in earlier periods. References to this effect were to be found, among others, in Seaboard Geographic Gazetteer compiled more than 1,700 years ago by Shen Ying of the State of Wu during the period of the Three Kingdoms. This was the world's earliest written account of Taiwan. Several expeditions, each numbering over ten thousand men, had been sent to Taiwan by the State of Wu (third century A.D.) and the Sui Dynasty (seventh century A.D.) respectively. Since early seventeenth century the Chinese people began to step up the development of Taiwan. Their numbers topped one hundred thousand at the end of the century. By 1893 (19th year of the reign of Qing Emperor Guangxu) their population exceeded 2.54 million people in 507,000 or more households. That was a 25-fold increase in 200 years. They brought in a more advanced mode of production and settled the whole length and breadth of Taiwan. Thanks to the determined efforts and hard toil of the pioneers, the development of the island as a whole greatly accelerated. This was the historical fact of how Taiwan, like the other parts of China, came to be opened up and settled by the Chinese people of various nationalities. From the very beginning the Taiwan society derived from the source of the Chinese cultural tradition. This basic fact had not changed even during the half century of Japanese occupation. The history of Taiwan's development is imbued with the blood, sweat, and ingenuity of the Chinese people including the local ethnic minorities.

Chinese governments of different periods set up administrative bodies to exercise jurisdiction over Taiwan. As early as in the mid-12th century the Song Dynasty set up a garrison in Penghu, putting the territory under the jurisdiction of Jinjiang County of Fujian's Quanzhou Prefecture. The Yuan Dynasty installed an agency of patrol and inspection in Penghu to administer the territory. During the mid- and late 16th century the Ming Dynasty reinstated the once abolished agency and sent reinforcements to Penghu in order to ward off foreign invaders. In 1662 (first year of the reign of Qing Emperor Kangxi) General Zheng Chenggong (known in the West as Koxinga) instituted Chengtian Prefecture on Taiwan. Subsequently, the Qing government expanded the administrative structure in Taiwan, thereby strengthening its rule over the territory. In 1684 (23rd year of the reign of Emperor Kangxi) a Taiwan-Xiamen Patrol Command and a Taiwan Prefecture Administration were set up under the jurisdiction of Fujian Province. These in turn exercised jurisdiction over three counties on the island: Taiwan (present-day Tainan), Fengshan (present-day Gaoxiong) and Zhuluo (present-day Jiayi). In 1714 (53rd year of the reign of Emperor Kangxi) the Qing government ordered the mapping of Taiwan to determine its size. In 1721 (60th year of the reign of Emperor Kangxi) an office of imperial supervisor of inspecting Taiwan was created and the Taiwan-Xiamen Patrol Command was renamed Prefecture Administration of Taiwan and Xiamen, incorporating the subsequently-created Zhanghua County and Danshui Canton. In 1727 (5th year of the reign of Emperor Yongzheng) the administration on the island was reconstituted as the Prefecture Administration of Taiwan (which was later renamed Prefecture Command for Patrol of Taiwan) and incorporated the new Penghu Canton. The territory then became officially known as Taiwan. In order to upgrade the administration of Taiwan, the Qing government created Taibei Prefecture, Jilong Canton and three counties of Danshui, Xinzhu and Yilan in 1875 (1st year of the reign of Emperor Guangxu). In 1885 (11th year of the reign of Emperor Guangxu), the government formally made Taiwan a full province covering three prefectures and one subprefecture and incorporating 11 counties and 5 cantons. Liu Mingchuan was appointed first Governor of Taiwan. During his tenure of office, railways were laid, mines opened, telegraph service installed, merchant ships built, industries started and new-style schools set up. Considerable social, economic and cultural advancement in Taiwan was achieved as a result.

After the Chinese people's victory in the war against Japanese aggression in 1945, the Chinese government reinstated its administrative authority in Taiwan Province.

Chinese on both sides of the Taiwan Straits carried out a prolonged, unremitting struggle against foreign invasion and occupation of Taiwan. Since the late 15th century Western colonialists started to grab and conquer colonies in a big way. In 1624 (4th year of the reign of Ming Emperor Tianqi) Dutch colonialists invaded and occupied the southern part of Taiwan. Two years later Spanish colonialists seized the northern part of Taiwan. In 1642 (15th year of the reign of Ming Emperor Chongzhen) the Dutch evicted the Spaniards and took over north Taiwan. The Chinese people on both sides of the Straits waged various forms of struggle including armed insurrections against the invasion and occupation of Taiwan by foreign colonialists. In 1661 (18th year of the reign of Qing Emperor Shunzhi) General Zheng Chenggong (Koxinga) led an expedition to Taiwan and expelled the Dutch colonialists from the island in the following year.

Japan launched a war of aggression against China in 1894 (20th year of the reign of Qing Emperor Guangxu). In the ensuing year, as a result of defeat the Qing government was forced to sign the Treaty of Shimonoseki, ceding Taiwan to Japan. This wanton betrayal and humiliation shocked the whole nation and touched off a storm of protests. A thousand or more candidates from all 18 provinces including Taiwan who had assembled in Beijing for the Imperial Examination signed a strongly-worded petition opposing the ceding of Taiwan. In Taiwan itself, people wailed and bemoaned the betrayal and went on general strikes. General Liu Yongfu and others of the garrison command stood with Taiwan compatriots and put up a fierce fight against the Japanese landing forces. To support this struggle, people on the mainland, particularly in the southeastern region, showed their solidarity by generous donations or organizing volunteers to Taiwan to fight the Japanese forces. Taiwan compatriots never ceased their dauntless struggle throughout the Japanese occupation. Initially, they formed insurgent groups to wage guerrilla warfare for as long as seven years. When the Revolution of 1911 overthrew the Qing monarchy they in turn lent support to their mainland compatriots by staging more than a dozen armed insurrections. The 1920s and 1930s witnessed surging waves of mass action sweeping across the island against Japanese colonial rule.

In 1937 the Chinese people threw themselves into an all-out war of resistance against Japanese aggression. In its declaration of war against Japan, the Chinese Government proclaimed that all treaties, conventions, agreements, and contracts regarding relations between China and Japan, including the Treaty of Shimonoseki, had been abrogated. The declaration stressed that China would recover Taiwan, Penghu and the four northeastern provinces. After eight years of grueling war against Japanese aggression the Chinese people won final victory and recovered the lost territory of Taiwan in 1945. Taiwan compatriots displayed an outburst of passion and celebrated the great triumph of their return to the fold of the motherland by setting off big bangs of fireworks and performing rites to communicate the event to their ancestors.

The international community has acknowledged the fact that Taiwan belongs to China. The Chinese people's war of resistance against Japanese aggression, being part of the world-wide struggle against Fascism, received extensive support from people all over the world. During the Second World War China, the United States, the Soviet Union, Great Britain, France and others formed an alliance to oppose the Axis of Germany, Japan and Italy. The Cairo Declaration issued by China, the United States and Great Britain on 1 December 1943 stated: "It is the purpose of the three great Allies that Japan shall be stripped of all the islands in the Pacific which she has seized or occupied since the beginning of the First World War in 1914, and that all the territories Japan has stolen from the Chinese, such as Manchuria, Formosa [Taiwan] and the Pescadores [Penghu], shall be restored to China." The Potsdam Proclamation signed by China, the United States and Great Britain on 26 July 1945 (subsequently adhered to by the Soviet Union) reiterated: "The terms of the Cairo Declaration shall be carried out." On 15 August of the same year, Japan declared surrender. The instrument of Japan's surrender stipulated that "Japan hereby accepts the provisions in the declaration issued by the heads of the Governments of the United States, China and Great Britain on July 26, 1945 at Potsdam, and subsequently adhered to by the Union of Soviet Socialist Republics." On 25 October the ceremony for accepting Japan's surrender in Taiwan Province of the China war theater of the Allied powers was held in Taibei. On the occasion the chief officer for accepting the surrender proclaimed on behalf of the Chinese government that from that day forward Taiwan and the Penghu Archipelago had again been incorporated formally into the territory of China and that the territory, people, and administration had now been placed under the sovereignty of China. From that point in time forward, Taiwan and Penghu had been put back under the jurisdiction of Chinese sovereignty.

Since the founding of the People's Republic of China, 157 countries have established diplomatic relations with China. All these countries recognize that there is only one China and that the Government of the People's Republic of China is the sole legal government of China and Taiwan is part of China.