What is the historical basis for the claim that "Taiwan has always been part of China"?

When Mao drove Chiang Kai-shek out of China, the latter took over Taiwan by military force. What would be the need to do that if it was a part of China? He then required all Taiwanese to join the army because he wanted to go back and take over the mainland. That never happened, so the pure Chinese came in 1949~1954 period, when Chiang Kai-shek fled to Taiwan with 0.94 million Chinese refugees until then the island was made up and controlled by the Taiwanese.

I see it as it's own country and not a part of China. Mainland China sees it the other way. When I lived there in the 1960's the island of Taiwan and China were still shooting at each other each day just to prove they were still at war. There wasn't an invasion from either side, just shelling. There were no free elections, Taiwan became a military dictatorship.

Regardless of territorial history, the PRC's claim of Taiwan stems from the civil war that had begun in China before Japan invaded in the 1930's, and resumed when war with Japan ended.

The forces were the Kuomintang, the government formed by Sun-Yat Sen during the Xinhai Revolution of 1911 when the last Qing dynasty was overthrown and the colonizing European powers evicted. During WW2, the Kuomintang government was led by Chiang Kai-Shek.

And the communists under Mao Tse-Tung. Obviously, the communists prevailed. Chiang took his remaining forces and government, and those citizens closely allied with the Kuomintang government (who probably would have been shot by the communists), and moved en mass to the large island of Taiwan, which had been a Japanese territory, taken from the Qing dynasty by Japan during the 1895 Sino-Japanese war.

As the early PRC had no real amphibious war capability, the fleeing ROC (Republic of China) government was able to consolidate its position and military strength, to where an invasion of Taiwan would be very costly.

For a long time after that war, the ROC maintained a seat on the UN's security council, as the representative of the Chinese people. That was lost when the US and the PRC warmed relations in the 1970's, and the PRC was given the security council seat.

So, technically speaking, the Chinese Civil War of 1949-1950 is still going on, as the Kuomintang government was never fully defeated, and still exists (and thrives) today.

Viewed in the context of how the two nations came to be, the PRC's claim isn't so much for the land, but authority over the Chinese people who live on that land, and especially final defeat of the Kuomintang government after almost 70 years.

Interesting perspective on this situation today: Many successful Chinese businesses are actually owned and operated by Taiwanese citizens. One reason: Citizens living in the PRC, which had been closed to the world for decades, had little experience in international business and finance when China began to open up economically to the rest of the world, while their counterparts on Taiwan had been selling goods to the western nations for a very long time.

The PRC maintains a 'one China' policy, that there is only one Chinese government and that's them. They are willing to look the other way for very successful Taiwanese owned businesses operating in China, like Foxconn, who makes a lot of electronic equipment for Apple.

Not upsetting their productive business partners and throwing major employers into disarray is one reason the PRC would be very reluctant to attack the ROC today.

China hasn't always been China. Modern China is currently being ruled by insurrectionists. China can't handle what territories they already posess:

• negative side effects of industrialization
• famine
• poverty
• huge portions of the population uneducated and or living in 3rd world conditions
• disease
• population control problems
• problems with the culture leading to huge discrepancy with the male to female population ratio
• using extremely aggressive nationalist propaganda to placate the masses

These reasons are just the tip of the iceberg. All things considered, even if they did have legitimate historical claim to the region it would be irrelevant. Most Taiwanese have no interest in being part of China, in no small part because Taiwan is being poisoned by Chinese pollution and is under constant threat of Chinese invasion.

Historically, Chinese settlers only colonized parts of coastal Taiwan:

There is no legitimate claim to the territory. Outsiders relocated to already populated areas, largely integrated, only spread incrementally over a long period of time and only controlled a relatively small portion of the land.

I assume your question is: Since People's Republic of China (PRC) exists, was Taiwan considered as part of it?

It is more like a political question than historical, since the current situation of PRC and ROC (Republic of China) is still unsettled since the end of the civil war.

I am sure most of us know that People's Republic of China claims Taiwan, but it is de-facto independent country. So in a way Taiwan is part of PRC.

Importantly on the other hand maybe less people know that ROC renounced in 1992 the conquest of PRC-controlled territories as a national goal, there is still dispute over whether the constitution still gives legal support to a claim of sovereignty over all of China's pre-1949 territories, including Outer Mongolia and the entirety of the present PRC. From Wikipedia
So in a way PRC's territory belongs to ROC as well.

Objectively, these two territories function as separate countries. Separate governments, currency, foreign relations.

Taiwan's independence is recognized by various countries, and most of countries have unofficial relationship with Taiwan (without embassy), but there are couple of countries have completely official foreign relationship with Taiwan including embassy.

Taiwan's de-facto independence is reinforced by USA through Taiwan Relations Act accepted in 28th February 1979.

So the answer is "yes and no in the same time", entirely depends on political view. Also answer is no for practical way, they both do function as two separate countries.

This is not my answer but an invitation for history buffs to understand the history of Taiwan. It has been answered by a historian in Chinese & Global History -- Tonio Andrade of Emory Department of History.

How Taiwan Became Chinese - Dutch, Spanish, and Han Colonization in the Seventeenth Century (Columbia University Press, 2008). The entire book is available on Gutenberg.

Preface: Is Taiwan Chinese?

On March 26, 2005, I marched with thousands of Taiwanese against the Anti-Secession Law, passed two weeks before in Beijing. I had not intended to participate. My parents were to arrive that evening, and my wife and I were cleaning madly. But when we went out for groceries and found the streets pulsing with people, we joined in. The marchers were peaceful, powerful, and confident in their right to political expression. Since the lifting of martial law in 1987, Taiwan's political freedoms have grown steadily, and today it is the only truly democratic Chinese polity. It represents the best way forward for 1.3 billion people in mainland China.

As we marched I began to wonder whether I was right to call my book How Taiwan Became Chinese. Nowadays, some Taiwanese contend that Taiwan is not Chinese, rejecting their cultural kinship with people in mainland China. What right have I, an outsider, to suggest differently? More important, I worried that my title might help hawks in mainland China argue that Taiwan belongs to the People's Republic of China, and I strongly believe that Taiwan belongs to its people and should be whatever they decide. They're doing a great job ruling themselves.

Yet there is no doubt that Taiwan today is culturally Chinese. In the 1600s, people from China began settling there. Most were from the province of Fujian and spoke a dialect of Chinese known as Southern Min, but they were joined later by Hakka Chinese, and then, in the late 1940s, by around 2 million Mandarin speakers. Today, all but 2 percent of Taiwan's population belongs to one of these groups. Indeed, in many ways Taiwan is more Chinese than its assertive neighbor. Three decades of Maoism stripped away parts of mainland China's traditional culture, but Taiwan preserves customs, festivals, and schools of thought that were extinguished across the strait.

And if you'd lived your life in the Republic of China you'd have learned that Taiwan is an independent nation, the one true China, and that the rebel government in Beijing is illegally in power there (that may have been toned down now, but that used to be the line in the ROC).
Both are of course propaganda.

Truth is Taiwan wasn't "always" part of China because China didn't always exist. And yes, the government on Taiwan predates the government in Beijing, the latter being created by Maoist forces after WW2 when the ROC government is the direct descendent of the government that was in place in China before WW2, which was driven off the mainland by Mao and his revolutionaries during the civil war.

So in a way both are right. Taiwan was for a long time part of imperial China, but never was part of the PRC which was built on the ruins of what was left after WW2 and the Chinese civil war that followed it.
And the old ROC claim to the mainland has validity based on the same history.

You'd say after 70 years almost it's time to let matters rest and for each to recognise the independence of the other.