With very few exceptions, all vocal performances heard during the movie were original recordings of the 1930's group. The old material was de-noised and digitally enhanced.
In this film, Heino Ferch and Ulrich Noethen play Jews who are persecuted by the Nazi Regime. In Downfall (2004), Ferch played Albert Speer and Noethen played Reichsführer-SS Heinrich Himmler.
Ben Becker and Meret Becker, who play lovers here, are in real life brother and sister. Otto Sander (1941-2013), who plays Bruno Levy, was the Becker siblings' real-life stepfather.
When the Comedian harmonists hold their concert aboard the USS Saratoga, a parade of ships is seen, with the leading ship being an AEGIS class cruiser.
Harry Frommermann: [to Robert Biberti after a successful concert, where Harry made the audience laugh]
Am I a donkey, cause I'm your friend or am I your friend because I'm a donkey?