Constitution in 1991, and there have been a number of judicial interpretations made to take into account the fact that the Constitution covers a much smaller area than originally envisioned. The government in Taipei officially asserts to be the sole legitimate government of all of China, which it defined as including Taiwan, mainland China, and outer Mongolia. In keeping with that claim, when the KMT fled to Taipei in 1949, they re-established the full array of central political bodies, which had existed in mainland China in the de jure capital of Nanjing (Nanking). While much of this structure remains in place, the President Lee Teng-hui in 1991 unofficially abandoned the government's claim of sovereignty over mainland China, stating that they do not "dispute the fact that the Communists control mainland China." However, the National Assembly has not officially changed the national borders, as doing so may be seen as a prelude to formal Taiwanese independence. The People's Republic of China has several times threatened to start a war if the government of Taiwan formalizes independence; as in the Anti-Secession Law. Neither the National Assembly nor the Supreme Court has actually defined what the term "existing national boundaries," as stated in the constitution, actually means. The latter refused to do so claiming that it is a "major political issue". Political history Taiwan under Japanese rule After the First Sino-Japanese War, China were forced to cede the island of Formosa to Japan. Under Japanese rule, Taiwan has its governor general as its head of government under the constitutional monarchy led by the Emperor. Taiwanese citizens in Formosa and Pescadores were Japanese citizens until the end of World War II in 1945. Republic of China on Mainland China, 1911–1949 The original founding of the Republic centered on the Three Principles of the People (): nationalism, democracy, and people's livelihood. Nationalism meant the Chinese people standing up against Manchu rule and Japanese and Western interference, democracy meant elected rule modeled after Japan's parliament, and people's livelihood or socialism, meant government regulation of the means of production. Another lesser known principle that the Republic was founded upon was five races under one union (五族共和), which emphasized the harmony of the five major ethnic groups in China as represented by the colored stripes of the original Five-Colored Flag of the Republic. However, this "five races under one union" principle and the corresponding flag were abandoned in