When Did Masao Koga Die?

Masao Koga was a Japanese composer, mandolinist, and guitarist of the Shōwa era who was dubbed "Japan's Irving Berlin" by Universal Press Syndicate. His melancholy style, based upon Nakayama Shimpei's yonanuki scale, was popularly known in Japan as "Koga melody" . He was awarded the Order of the Sacred Treasure and the People's Honor Award for his contributions to Japanese music.