Taiwans history with China spans ~400 years. The Ming Dynasty pushed out the dutch and had some settlements, but this was at the end of the Ming Dynasty.

After the Qing Dynasty took over they did nothing with Taiwan. The Qing Dynasty called Taiwan a ball of mud in the sea not worth the effort of China. There was some people who travelled and setup in Taiwan but ultimately the Qing Dynasty never controlled Taiwan and was in constant conflict with the locals.

In 1887 they decided to call Taiwan a Provience in order to defer Japan from attacking. During this time they tried a little bit to build Taiwan, but again, ultimately not controling the Island.

When Japan attacked, they threw their hands in the air and ceeded to Japan. Japan wasn't even convinced that China controlled Taiwan, and China convinced Japan they did by saying there are other countries where the governments cannot control the indigenous people.

Japan took over and ruled with an iron fist.

After the war the US handed Taiwan to KMT as temporary administer the Island until the fate of the Island had been decided. This part has never happened and is why the US is ambigious on the status of Taiwan.

So no. The populations were NEVER unified in any way.