Second-unit director Richard Rosson traveled to Fort Tinihir in Morocco for location shooting. There he met 900 German members of the French Foreign Legion. They had all been members of Gen. Erwin Rommel's famed Afrika Korps during World War II. After the war ended, these men, who were now POWs under French control, were given a choice by the French to either enlist in the French Foreign Legion or return home to a now-ruined Germany. Most chose to sign on as legionnaires.
Extras were provided by the French Foreign Legion and the Moroccan Spahi cavalry.
According to director Jean Delannoy in his autobiography, first assistant Roger Calon and second assistant Jean-Paul Gudin were both killed in a jeep accident during the making of this film.
The second unit traveled to Morocco in December 1947 and spent over four months shooting battle and chase scenes--and expending 85,000 feet of film.
A rare example of an American film production being given official assistance from the French Foreign Legion.