The background page for Taiwan says:
Background: In 1895, military defeat forced China to cede Taiwan to Japan. Taiwan reverted to Chinese control after World War II. Following the Communist victory on the mainland in 1949, 2 million Nationalists fled to Taiwan and established a government using the 1946 constitution drawn up for all of China.
This part contains a couple of errors. Taiwan has never "reverted" to Chinese control (it was never under Chinese control, being loosely held by the Qing Dynasty, Manchus who ruled China until 1911); the sovereign power over Taiwan after WWII was Japan, which remained sovereign until April 1952, when, under the San Francisco Peace Treaty, it gave up sovereignty. Since no recipient of Taiwan's sovereignty is named in the treaty, the status of Taiwan is currently undefined, the position of all the major powers except China in the postwar period.
The ROC occupied Taiwan on behalf of the Allied powers in 1945. It was governed by a representative of the Chiang Kai-shek regime until the ROC government moved there in 1949.
Perhaps the background can be rewritten to reflect the island's disputed status. Something like
"In 1895 the Qing Dynasty ceded Taiwan to Japan after military defeat. After a half-century of Japanese colonialism, Taiwan was occupied by the ROC in 1945 following the end of WWII. In 1949 the Chinese Nationalists lost the civil war to the Communists, and fled to Taiwan."
The Japanese colonial period was an important one for the development of the island and deserves mention.