Attention to detail was particularly important to the producers, so all of the naval procedures depicted in this movie are completely accurate. The scene where Harwood meets with his Captains on board the Ajax, however, was a fictitious one, created in order to explain the situation to the audience.
The U.S.S. Salem was a World War II-vintage Des Moines-class heavy cruiser, armed with nine eight-inch guns. In this movie, we can also see the three-inch AA guns installed to combat Kamikaze attacks.
The original English version of this movie omits the tragic final act of the story. A few days after scuttling his own ship, German Captain Hans Langsdorff committed suicide in a hotel room in Buenos Aires, Argentina. He was dressed in full uniform and wrapped in the battle flag of his sunken vessel. In the German dubbed version, the final voiceover was changed to explain what happened to Langsdorff.
The midshipmen's quarters were empty because Captain Langsdorff had promoted all of his midshipmen to ensigns in order to make room for his prisoners.
The photo of the Admiral Graf Spee in the Captain's cabin was taken at the Fleet Review in Spithead in 1937. The two ships in the background are H.M.S. Hood and H.M.S. Resolution.