Whenever I stumble across a song I like on youtube I download it into my personal music folder, I started this practice more than 4 years ago and I accumulated a large amount of socialist music from very niche spaces, spanning across a wide variety of languages. Because I see that nobody else is doing this specific thing on this site, I feel compelled to share this collection track by track, maybe it will lead to someone else also feeling the same inspiration that I felt when first listening to it.
The Sacred War was the song made by the Red Army Choir mere days after the start of the Great Patriotic War, when the fascist armies of Europe launched the largest land invasion in the history of the world against the Soviet Union.
It was a brutal war waged with the sole purpose of enslaving and exterminating the Soviet people and the original song conveyed that feeling perfectly, for the Soviet people it was not only a war to defend themselves, their families and the socialist project, but a sacred war to put down the vile ideology of fascism that was poised to bring a new dark age over humanity.
The song became one of the most famous tracks from the WW2 era, inside the Soviet Union the song was so widely circulated some say it effectively became its unofficial anthem during the war. Like Katyusha it was translated into numerous languages, including German where the famous East German singer Ernst Busch covered it.
This version is much more different, however. Sung by Chris Peterka in German, his version becomes a slow, mournful and melancholic soliloquy, almost resembling a campfire song. I personally interpret it as a song mourning the fate of the Soviet Union, as it was the nazi invasion that took the lives of over 26 million soviet people and was what I would argue to be the first domino that led to its eventual collapse less than 50 years later.
I found a YouTube link in your post. Here are links to the same video on alternative frontends that protect your privacy: