Allegedly Russian and Ukrainian soldiers singing "Katyusha" on the front lines.I looked up the song. The song was popular in WW2, is about a Russian woman called Katyusha. Standing on a steep riverbank, she sings a song to her beloved, a soldier serving far away. The theme of the song is that the soldier will protect the Motherland and its people while his grateful girl will keep and protect their love.

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