This rather eerie military song (軍歌 gunka) Umi Yukaba 海行かば was based on an ancient 和歌 waka poem by Ōtomo no Yakamochi and put to music by Nobutoki Kiyoshi in 1937. Popular throughout WWII, Umi Yukaba was sung by departing Kamikaze pilots (神風) during the last stages of the Pacific War.
If I go away to the sea, I shall be a corpse washed up.
If I go away to the mountain, I shall be a corpse in the grass.
But if I die for the Emperor, It will not be a regret.