Hogan's Heroes (1965) shared many similarities to this movie. The regular characters in Hogan's Heroes (1965) are characters straight out of this movie, and many of the antics in the series are things that happen in the movie. However, there is no mention of Charles Coward's autobiography or of this movie in any of the "Hogan's Heroes" credits.
Nigel Stock, who plays Cole, mentions digging the tunnel 25 feet deep to stay hidden from the microphones. In The Great Escape (1963), he played Cavendish, the surveyor, who miscalculated the length of the tunnel.
The tagline claims that Charles Coward is the only man to get an Iron Cross from the enemy. This is untrue. Double agent Eddie Chapman was awarded the Iron Cross by the Nazis while working loyally for the British.
The 2-6-4T LMS locomotive involved in the crash was bought by MGM for £3,500 from the railroad. The studio then turned around and sold it for scrap for £5,000.
The first P.O.W. camp seen is supposed to be Stalag VIII-B in Lamsdorf, Germany (now Lambinowice, Poland). In use from 1939 to 1945, over one hundred thousand P.O.W.s from more than a dozen Allied nations passed through this camp. It was reached by the Soviet Army on March 17, 1945.