Yukio Mishima (三島 由紀夫, Mishima Yukio), born Kimitake Hiraoka (平岡 公威, Hiraoka Kimitake, 14 January 1925 – 25 November 1970), was a Japanese author, poet, playwright, actor, model, Shintoist, nationalist, and founder of the Tatenokai (楯の会, "Shield Society"). Mishima is considered one of the most important post-war stylists of the Japanese language. He was considered for the Nobel Prize in Literature five times in the 1960s—including in 1968, but that year the award went to his countryman and benefactor Yasunari Kawabata. His works include the novels Confessions of a Mask and The Temple of the Golden Pavilion, and the autobiographical essay Sun and Steel. Mishima's work is characterized by "its luxurious vocabulary and decadent metaphors, its fusion of traditional Japanese and modern Western literary styles, and its obsessive assertions of the unity of beauty, eroticism and death", according to author Andrew Rankin.
Mishima's political activities made him a controversial figure, which he remains in modern Japan. From his mid-30s, Mishima's right-wing ideology and reactionary beliefs were increasingly evident. He was proud of the traditional culture and spirit of Japan, and opposed what he saw as western-style materialism, along with Japan's postwar democracy, globalism, and communism, worrying that by embracing these ideas the Japanese people would lose their "national essence" (kokutai) and their distinctive cultural heritage (Shinto and Yamato-damashii) to become a "rootless" people. Mishima formed the Tatenokai for the avowed purpose of restoring sacredness and dignity to the Emperor of Japan. On 25 November 1970, Mishima and four members of his militia entered a military base in central Tokyo, took its commandant hostage, and unsuccessfully tried to inspire the Japan Self-Defense Forces to rise up and overthrow Japan's 1947 Constitution (which he called "a constitution of defeat"). After his speech and screaming of "Long live the Emperor!", he committed seppuku.
Source : Wikipedia
