The original UK title was "A Hill in Korea", but was changed to "Hell in Korea" for distribution in the U.S.
Sir Michael Caine is a veteran of the Korean War. He has sometimes said in interviews that he was, as a result of this, also the film's technical adviser, but this is almost certainly an exaggeration. He may have mentioned one or two of his Korean experiences in conversation, but that's hardly what is meant by "technical adviser". The future film producer Richard Goodwin is usually mentioned as the movie's military adviser, although he's not credited as such.
Back in the summer of 1955, the British production crew of this movie, under director Julian Amyes, was on location on the mountain of Montejunto, Portugal, chosen as the facsimile location to South Korea, due to its geographical similarities, even though Sir Michael Caine, who served as technical consultant and actor on the production, begged to differ. Joseph Valador, who recently turned 85 years old, served as a liaison and interpreter between the British filming crew and Portuguese. Joseph arranged to have the Portuguese military planes fly over the designated shooting locations. He also served as an assistant to director Julian Amyes in the critical scene where the Koreans burn down the village, acting the part as the Korean leader. Joseph was thanked by Amyes for his excellent direction and communication with the Portuguese end of the shoot, having saved the crew from re-building the village set. Joseph coordinated the flying of the Portuguese Air Force, which was used in the jet flying and bombing scene. Also to be noted was his involvement as an extra, where he acted the part of the Korean soldier falling off the horse when the platoon is discovered while hiding in the brush.
The first theatrical movie to portray British troops in action during the Korean War.
Opening credits prologue: "This film is dedicated to National Servicemen and Drafted Men of the Free Nations past, present and to come."