Scenes of the parliament building were shot on location and included Nazi flags and banners, displayed for the first time since WWII ended.
The producers wanted to use members of His Majesty The King's Guard as Nazi extras due to their marching and military drill skills. However, army commanders refused because they didn't want serving members of the King's Guard to dress up in Nazi uniform or portray Nazis.
Holds the record for the most seen Norwegian movie in theaters, with 184,288 admissions in its opening week, overtaking previous record holder The Kautokeino Rebellion (2008).
In the movie, Gregers Gram talks about the idea that someone should make a statue of him, and put it somewhere fancy, like in front of City Hall in Oslo. This is a clever joke, as there really is a statue of Gregers Gram outside Njårdhallen (the Njaard sports hall).
The king of Norway, Haakon VII, speaks Danish. He was in fact a Dane, a son of the Danish king Frederik VIII.
Thomas Nordseth-Tiller: The writer plays one of the two undercover Gestapo agents shot at plasskafeen.
Espen Sandberg, Joachim Rønning: In the scene where Max and Gregers receives the war cross from King Haakon, they are standing to the right of the king. Sandberg is the one handing him the medals.