At least 14,000 extras and 15,000 animals were used in this movie.
Cecil B. DeMille picked Charlton Heston for the role of Moses because he bore a resemblance to Michelangelo's statue of Moses in Rome, Italy. Heston played Michelangelo in "The Agony and the Ecstasy (1965)".
Producer/director Cecil B. DeMille suffered a heart attack during production, after climbing 130 feet to check a faulty camera perched on one of the giant gates used during the exodus sequence. He took two days off, then returned to work, against his doctor's orders, to complete this movie.
When Yul Brynner was told he would be playing Pharaoh Rameses II opposite Charlton Heston's Moses, and that he would be shirtless for most of the movie, he began a rigorous weightlifting program because he didn't want Heston to physically overshadow him. That explains his buffer-than-normal physique during The King and I (1956), which he made just after this film. Heston later said that Brynner gave the best performance in this movie.
According to Hollywood lore, while filming the orgy sequence that precedes Moses' descent from Mount Horeb with the two stone tablets on which the Ten Commandments are engraved, producer and director Cecil B. DeMille was perched on top of a ladder delivering his customarily long-winded directions through a megaphone to the hundreds of extras involved in the scene. After droning on to the extras for several minutes, DeMille was distracted by one young woman who was talking to another woman standing next to her. DeMille stopped his speech and directed everyone's attention to the young woman. "Here", DeMille said, "we have a young woman whose conversation with her friend is apparently more important than listening to her instructions from her director while we are all engaged in making motion picture history. Perhaps the young woman would care to enlighten us all, and tell us what the devil is so important that it cannot wait until after we make this shot." After an embarrassed pause, the young woman spoke up and boldly confessed, "I was just saying to my friend here, 'I wonder when that bald-headed old fart is gonna call 'Lunch!'" Nonplussed, DeMille stared at the woman for a moment, paused, then lifted his megaphone and shouted, "Lunch!"
H.B. Warner: Amminadab, an old Hebrew man about to die in the desert, during the Exodus sequence. At the time of filming, Warner was as frail in real life as he appeared in this movie. Producer and director Cecil B. DeMille wanted Warner to play The Blind One so badly that he arranged for an ambulance to pick Warner up at his nursing home and bring him to the set for his cameo.