It was included in the original Broadway run and was first performed by the Von Trapp children, played by Kathy Dunn, David Gress, Evanna Lien, Mary Susan Locke, Lauri Peters, Marilyn Rogers, Joseph Stewart, and Frances Underhill.
"So Long, Farewell" is a simple composition that effectively exploits the children's higher voices and innocent charm.
It depicts a Goebbels type family eating dinner in a bunker next to the Swastika Christmas tree from John Heartfield's O Tannenbaum im deutschen Raum, wie krumm sind deine äste!.
According to Laibach the symbolism of this video is that the Von Trapp family never left Nazi controlled Austria but simply went "underground" much like how North Koreans are trapped in their totalitarian country.
"[1] This music video also includes a reference to Josef Fritzl with the father leading his children to the basement.