Zhejiang or Chekiang is a de jure province in the Republic of China according to the ROC law, as the ROC government formally claims to be the legitimate government of the whole China. Founded after the collapse of the Qing dynasty, it was de facto abolished after the ROC armed forces, ROC government officials and local residents were evacuated from Dachen to Taiwan in 1955 following the military defeat of the ROC by People's Liberation Army forces of the newly-founded People's Republic of China during the Battle of Dachen Archipelago.

The Dachen Islands, Tachen Islands or Tachens are a group of islands off the coast of Taizhou, Zhejiang, China, in the East China Sea. They are administered by the Jiaojiang District of Taizhou. Before the First Taiwan Strait Crisis in 1955, the islands were administered by the Republic of China (ROC).