Esmond Knight, who plays the captain of the HMS Prince of Wales, actually served as an officer on board her and was injured during the battle.
In the movie the fleet is ordered to proceed under the assumption that the Bismark is going to Brest, this is shown as a hunch from Captain Shepard. This is actually not true as that information was provided to the Admiralty by the code breakers in Bletchley Park. However the movie came out in 1960 and that information was not declassified until the mid 70's so there was no way for them to know it at the time.
To help give the film a sense of gravitas, Edward R. Murrow was added to the cast. Murrow was one of the most famous and respected correspondents during (and after)) WWII, during which he covered the war raging in Europe, including the North Atlantic; Murrow also shot introductory footage for the film's trailer.
The opening shows actual newsreel footage of the Bismarck when it was launched in Hamburg, Germany, in 1939.
The producers knew that the use of miniatures and explosions would have to look very realistic to be successful. They hired Howard Lydecker, one of the legendary Lydecker brothers--the other was Theodore Lydecker--who were generally considered to be the best special effects team in the industry. They had spent decades perfecting their craft at Republic Pictures.
This film's closing epilogue states: "This film was based upon actual operations against the German battleship, "Bismarck". Grateful acknowledgment is made to the Admiralty for their most generous help, advice and co-operation. The character called Captain Shepard is completely fictitious and is in no way intended to depict Captain R. A. B. Edwards (now Admiral Sir Ralph Edwards, K.C.B., C.B.E.) who was the actual Director of Operations at the time of the "Bismarck" engagement."
'Kenneth More (I)' was offered The Guns of Navarone (1961) because of his work in this film.
Most of the external shots of the battleships were reported to have been shot on board HMS Vanguard (the last British battle ship in service).
According to special effects cinematographer L.B. Abbott, the miniatures were photographed with spherical (non-anamorphic) lenses. This made it easier to force the perspective of the image to make the miniatures appear bigger and further apart. The conversion of the spherical footage to CinemaScope required the use of an optical printer with an anamorphic lens. This method of shooting with spherical lenses, yet converting the footage to anamorphic, is now commonly used and is called Super 35.
Prior to the release of the movie, a song of the same title sung by Johnny Horton was released in the United States to promote the film. This song never appears in the actual film. Excerpts from the song were used in the US trailer.
Bernard Lee (Firing Officer) played James Bond's superior M in the first eleven Bond films from Dr. No (1962) to Moonraker (1979) (1979)_ whilst Robert Brown (Gunnery Officer on George V) succeeded him in the role in Octopussy (1983), A View to a Kill (1985), The Living Daylights (1987) and Licence to Kill (1989).
Dana Wynter, the actress who plays Officer Anne Davis, was actually born in Berlin as Dagmar Winter.
Three years earlier in 1957, three of the stars of this film (Kenneth More, Laurence Naismith and Michael Goodliffe) all starred together in another film about the sinking of a famous ship, the Titanic, in A Night To Remember.