There were a number of very popular songs and singers during the war, Vera Lynn, Marlene Dietrich, Lucy Mann, Lale Anderson, Edith Piaf (although I don't believe she was well known outside of France and Germany until after the war?).
Famous songs would be "We'll meet again", "La Vie en Rose", "On a wing and a prayer", and of course "Lili Marlene", although the German version is personally my favorite.
What about "We're Gonna Hang Out the Washing on the Siegfried Line"?
Personally, I like Guy Lombardo's "And the Band Played On," but that's just me.
"As we sat there in that basement, with lights flickering and dust falling with every muffled explosion occurring in the street above us, we listened to the strokes of the paino playing on the radio. This seemed only to compound the hopelessness filling the air, as thick as humidity. I sat in a red chair, smoking a cigarette, thinking about the past week's events. Kreiger, Wittmann, Weir, Fuchs, and Heiglemann were dead. All of them. All my friends, with whom I had shared so much agony, were gone forever." - Excerpt from storyline for "At What Cost"
