High Quality Content by WIKIPEDIA articles! The Republic of China (ROC), commonly known as Taiwan (see below), is a unitary sovereign state located in East Asia. Originally based in mainland China, the Republic of China currently governs the island of Taiwan (Formosa), which forms over 99% of its current territory, as well as Penghu, Kinmen, Matsu and other minor islands. Neighboring states include the People`s Republic of China (PRC) to the west, Japan to the east and northeast, and the Philippines to the south. Its capital city is Taipei.