The concept of "national language" was an invention closely associated with the advent of national states in modern times. In the last hundred years Taiwanese collectively experienced two national-language movements. The first one took place in the Japanese colonial period; the second occurred when Taiwan was taken over by the Nationalist government of China. The two movements promoted respectively Japanese and Mandarin. Both languages were no mother tongues of Taiwanese of Fukien origins, Hakkas ort the aborigines. This article analyzes the first Taiwanese experience of specking a national language. Before the Japanese language was introduced to the island by the colonizer, Taiwan was a society where different ethnic groups spoke their own languages-Funkenese, Hakka and Austronesian languages. The main goal of Japancese colonial education in Taiwan was to teach Taiwanese the Japanese language-the kokugo. Through the elementary school system and outside-school language programs, the number of Taiwanese who were able to converse in Japanese increased as time progressed, thus bringing into existence a bilingual society. In 1937 the colonical government embarked on a complete Japanization movement known as the koominka und, one major goal of which was to transform Taiwan into a monolingual society where Japanese would be spoken by all . According to an official estimate, by the end of 1943 the population of "national-language speakers" execeeded 80% of the total population. In spite of possible inflations in this estimate, Japanese had become the "common language" among the young generation of Taiwanese at the end of World War II. Japan's surrender brought an abrupt end to the first national language movement, while a new one awaited the Taiwanese. Japanese-educated Taiwanese suffered tremendously in postwar Taiwan when Mandarin replaced Japanese as the national language. They became functionally illiterate. Under the political atmosphere of Nationalist rule, it is not exaggerating to say that they were a muted generation. When Taiwan went through a political liberation in the late 1980s, its languages went through a "language liberation." With the rise of Taiwanese nationalism in opposition to Chinese nationalism, the relationship between Fukeienese and Mandarin has become in a tense relationship. It remains to be seen whether Mandarin will lose its status as the national language of Taiwan.