Some of the details are in fact based on authentic extra-Biblical Jewish or Christian legends. DeMille says that the screenwriters had to rely on other writings through history to flesh out this part of the story. In Exodus the narrative skips from when Pharoah's daughter retrieves Moses from the water to when Moses kills an Egyptian who is beating one of the Hebrew slaves. As the director himself states in his introductory remarks at the start of the film, the Bible skips some 30 years of Moses' life. It's not purely an invention of the film either, as it was inspired by Jewish oral tradition about Dathan dating back hundreds if not thousands of years. Here, he becomes The Quisling, is responsible for the Golden Calf incident, and was responsible for driving Moses out of Egypt to begin with. Adaptational Villainy: Dathan played a more minor role in the Exodus account, leading a revolt against Moses and getting swallowed up by the ground.Ironically, in that role, Anna tells the story of Moses, and he responds, 'This Moses is a fool.' Incidentally, three years later, Brynner would go on to play King Solomon. Actor Allusion: Prior to playing the Pharaoh, Yul Brynner was running Siam and wooing the English tutor in both the Broadway musical and later the film.As a shepherd he prospers and becomes known for his honest dealings. The Ace: Moses is a peerless warrior, a wise diplomat and a brilliant architect.

The source material is the same (though this film might've been distilled through an extra novel), but the directions taken with it are very different. The dedicated and curious might want to compare this with The Prince of Egypt and Exodus: Gods and Kings.

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