Kurt Kreuger said that in the scene where he tried to escape back to his lines with the Sudanese sergeant (Rex Ingram) in pursuit, Ingram caught him and pressed his face into the sand to kill him, Kreuger almost passed out due to lack of air.
For much of the production, the cast and crew were based in Brawley, CA, a small town about 40 miles from the filming location. At the time, Brawley offered little in terms of evening diversions, so Humphrey Bogart hosted many of his colleagues in his suite at the Planter's Hotel. Other cast members described Bogart as outgoing, generous and an adept bartender, but the late-night drinking meant that Bogart arrived on set hung over and quarrelsome. The behavior led to clashes with director Zoltan Korda.
Humphrey Bogart had signed a new contract with Warner Brothers and one of the perks of his new deal was that he was allowed to act in one film per year outside of his home studio. He quite liked Harry Cohn, head of Columbia Pictures, and decided he would enjoy working on a Columbia-produced film. Bogart's friendly relationship with Cohn was noteworthy, as many members of the film industry found Cohn to be notoriously unpleasant and abrasive. Bogart's decision to work for Columbia, even in a one-film-per-year deal, was massive for the studio, which lacked the star power of its rivals. This film marked the first of several collaborations between Bogart and Columbia, at the rate of one per year. While he was on loan to Columbia, Bogart was the studio's biggest star.
The Sahara Desert in this movie was Borrego Desert in California, which is located in the Imperial Valley, north of the American-Mexican border. Filming also took place in Brawley--also in Imperial County--Chatsworth (in the San Fernando Valley) and the sand dunes of Yuma, AZ.
Two thousand tons of sand were transported to the set in order to create the feel of loose desert sand, as reported in the "New York Times". The newspaper also reported that shadows were spray-painted on desert hills to enable them to be seen more clearly by the audience. In addition, sand dune ripples were created by spray-painting the sand with light paint and then turning on a wind-machine.