It seems that a well known Croatian tune U boj, u boj from the opera Nikola Subic Zrinski by Ivan Zajc is taught in Japanese schools. Information by Mr. Nenad Bach, New York. Professor Vladimir Devidé, outstanding Croatian japanologist, considers this very probable: he remembered a very young boy walking on a Tokyo street Komaba, wearing a huge rucksack filled with books, and whistling the familiar melody - \"U boj, u boj\"! (this occured in 1961, during his first visit to Japan; personal information, 2004). Japanese choir composed of 1000 singers conducted by maestro Katsuaki Kozai sang \"U BOJ\" in the Kokugikan Hall in Tokyo in February 26, 2006. This concert attended by about 10,000 listeners has been organized among others by Croatian embassy in Japan. In the introduction to the concert it has been said that this very popular tune was brought to Japan by Croatian mariners (then within Austrian-Hungarian army), immediately after the end of the WWI. Namely, while retreating from the Russian Far East front, a taifoon carried their ship to Japanese coast near Kobe. The Japanese liked very much \"U BOJ\" sung by Croatian mariners, and since then it became very popular throughout Japan. http://www.croatianhistory.net/etf/uboj.html