"She was playing 'The Beer Barrel Polka,' so loud they must have been able to hear it in the garden, in the barracks, in the town."

The Beer Barrel Polka, or Roll Out the Barrel, is a popular song from World War II, composed by Jaromír Vejvoda in 1927.

The song is also known as 'Rosamunde' in Germany, or 'Škoda Lásky' in the original Czech. Here it is, played by a German band: