Nearly all the extras in this film were from the Royal Australian Air Force and The Royal Australian Army. For authenticity, the director made them shave off their mustaches which apparently weren't allowed in the German army in WW2.
Brian Trenchard-Smith commented that The Frenchman was played by Michael Massee, an American actor, who was born in Kansas City to French parents. Masse convinced him at the audition that he was French because he insisted the part would have to be played by a genuine Frenchman and he never broke cover on or off the set till the very last day of the 18-day shoot.
The tank used in the film is an M3 Lee, but has features of the variety used by the Australian Army during WW2. The standard US commander's cupola was deleted from the 37mm turret and a pintle mounted .30 caliber Browning machine gun was used in its place. Additionally the type of track used on the tank is track used by Commonwealth forces and not US forces.
In November 1942, Camp Laguna in Yuma, Arizona started as a major training site for George S. Patton's armored units. It was one of fourteen such camps built in the southwestern deserts to train United States troops during World War II. It was a major training facility for units engaged in combat during the 1942-1943 North African campaign. The desert was extremely suitable for the large-scale maneuvers necessary to prepare inexperienced American soldiers for combat against the highly trained and much feared German Afrika Korps in the North African desert.
In the iconic scene in the re-make of a Humphrey Bogart movie, the men lower canteen cups down the well to filled with the precious water that is only dripping at the bottom of the well. This, creating much tension as the full cups of water are raised inch by inch without spilling the water. This begs the question, why didn't they just send down their canteens down the well as the canteen have screw on caps?