When King Tutankhamen's tomb was found on November 4, 1922, the person in charge was George Herbert, 5th Earl of Carnarvon. Along with him was his daughter, Lady Evelyn Carnarvon. Rachel Weisz's character is named Evelyn Carnahan. Originally, her character was meant to be Evelyn Carnarvon. She and her brother were to be the children of the "cursed" Lord Carnarvon. The only evidence of this left in the film is in the line where Evelyn tells O'Connell that her father was a "very, very famous explorer". The Mummy novelization goes into a bit more detail on her back story.
The opening voice-over was originally intended to be read by Imhotep. Director Stephen Sommers later realized that Imhotep wouldn't be able to speak English, and gave the voice-over to Ardeth Bay instead.
In 2004, Universal Studios theme parks (Hollywood and Orlando) opened their "Revenge of the Mummy" rides based on both this movie and "The Mummy Returns" (2001). The rides became so popular, the lines would stretch into the main park with riders waiting for hours in the hot California or Florida sun. To alleviate the stress of waiting, when the lines would move, fans of the movie would wearily chant "Im-ho-tep. Im-ho-tep. Im-ho-tep." as the hypnotized townspeople do halfway through the movie.
In one scene, Beni is shown with a sackful of gold which he is trying to load onto a camel, and Beni pulls the camel by the reins but the camel doesn't budge; the camels all, for some reason, hated Kevin J. O'Connor.
"Imhotep" was actually the name of the architect who developed the first pyramids in ancient Egypt, most notably the Pyramid of Djoser at Saqqara around 2600 BC. His ability was such that he was later said to have descended from the gods. His name means "one who comes in peace"
Leonardo DiCaprio was rumoured to have been offered the role of Rick O'Connell. It's believed DiCaprio was said to have loved the script and wanted to be in the film, however he had already agreed to star in The Beach (2000). It's also been said that DiCaprio asked if The Beach could be delayed so he could film The Mummy, but producers refused. Ironically, filming of The Beach was delayed anyway.
Ardeth Bay, an anagram of Death By Ra, is the name of a sworn protector of mankind from the mummy Imhotep. However, in The Mummy (1932), Ardath Bey is the alter-ego of the mummy Imhotep (played by Boris Karloff) when he attempts to pass for a modern Egyptian (note the difference in the spelling of both names).
When Clive Barker was attached to the project, The film was intended to be a low budget horror film. Barker's vision for the film was violent, with the story revolving around the head of a contemporary art museum who turns out to be a cultist trying to reanimate mummies. George A. Romero was brought in with a vision of a zombie-style horror movie similar to Night of the Living Dead (1968), but this was considered too scary.
In the scene on the riverboat, Beni is thrown overboard and into the river by O'Connell; during filming, Kevin J. O'Connor helped Brendan Fraser to appear as though he was throwing him overboard by jumping up.
The plastic dummies used as dessicated corpses in the film to represent the Mummy's victims are the same as those used in the cult 1980s sci-fi film Lifeforce (1985). One character even refers to the Mummy sucking the 'lifeforce' out of people.
The locusts shown in the scene at Hamunaptra were mostly computer-generated, but a number of live grasshoppers were used for the shot; the grasshoppers were chilled in a refrigerator to make them more sluggish and easy to film.
In some scenes, characters who speak Arabic can be heard saying the same lines with different subtitles. This isn't as much a mistake as it is a throwback to the hero movies of old, in which foreign characters would say their lines in a different language to put up the illusion that they were speaking in said language.
The presence of living scarabs after centuries of isolation from food sources was better explained in an early version of the script; Imhotep was cursed to live forever when some of the sacred scarabs force themselves down his throat; and by eating him, the scarabs themselves were also cursed with everlasting life.
A different take of Ardeth Bay's introduction scene on top of the mountain was used later in the film when O'Connell and crew are crossing the desert at night. This time, the lighting was adjusted accordingly.
When Jonathan accidentally brings the military mummies to life and they go after O'Connell, Brendan Fraser runs across skeletons that are floating in water to get away from the mummies while making the same sort of noise that his character George makes from George of the Jungle.
Kevin J. O'Connor, who plays Beni, previously appeared in Law & Order: The Troubles (1991), in Law & Order's first season. That episode, like this movie, features a character named O'Connell who is generally addressed by surname only.
The lever-triggered slowly settling stone megaliths with sand pouring out like water, from which the characters must escape or be entombed alive, are based upon Howard Hawks' Land of the Pharaohs (1955), where Pharaoh Cheops's tomb is constructed to be sealed in this manner after he is placed within. Historically no such sophisticated engineering technology was ever employed.
The location shown in the scene where Imhotep and his minions corner the protagonists was an actual entrance to a thirteenth-century graveyard in Marrakesh. In the shots of the graveyard entrance, a manhole cover was used for the surviving protagonists to escape; the manhole was constructed for the film and had a large pad inside so that the actors would land on the pad and not hurt themselves.
The scene where O'Connell (Brendan Fraser) saves Evelyn from the sacrificial slab was filmed with Fraser fighting against invisible mummies. He meticulously choreographed his every movement, and all mummies were later added to the shot with computer-generated imagery, matching his moves.
A scene deleted from the film showed Rick, Evelyn and Jonathan crossing a field full of skeletons (belonging to Rick's fellow soldiers from the foreign legion and other fortune-seekers) before entering Hamunaptra. Another sequence that was cut occurred while Rick and Jonathan are trying to pry the chest containing the Book of Amun-Ra from the statue of Horus: suddenly, several mummies break through the floor and attack, but they quickly turn their attention to the chest. They open it and are immediately doused by pressurized acid. This scene explains why a hole in the floor suddenly appears between shots in the movie.