In 1965, at the height of the James Bond craze, "American-International Pictures" released this movie in the U.S. as "Operation Snafu". The title, as well as the advertising campaign, downplayed the comedic aspects of the movie, and by highlighting Sir Sean Connery's appearance (he was second-billed), suggested it was an espionage thriller in the tradition of the James Bond movies that were then breaking box-office records worldwide.
In the main titles, Cecil Parker is listed third and as "Starring". However, Cecil Parker only turns up in the last twenty minutes and has three scenes and twelve lines.
The fighting scenes in the woods were shot on Horsell Common in Surrey.
Four years after this film, Sean Connery and Alfred Lynch would once again play soldiers in "The Hill."