Dougray Scott was cast to play Wolverine. He had to leave the project because of his work on Mission: Impossible II (2000).
Hugh Jackman took cold showers to help him create the character Wolverine`s trademark "berserk rage."
There were three types of Wolverine claws - plastic, wood, and steel - and more than 700 individual claw blades were used by Hugh Jackman and his four stunt doubles.
When in full Mystique makeup, about 60 percent of Rebecca Romijn`s body was covered in prostheses.
Most of the eye effects were done by using special contact lenses that the actors found very uncomfortable to wear. Rebecca Romijn-Stamos (Mystique) could only wear her lenses for an hour at a time and had only 10% vision. Halle Berry (Storm) was supposed to wear opaque white lenses for the scenes where she uses her weather-control powers. However, she found the lenses unbearable, so her eye effects had to be done entirely through CGI.
Ten Wolverine costumes were built out of thick leather and PVC, and were designed to take a beating. All of them were destroyed to some extent during filming.
Hugh Jackman had to undergo training from a hand-to-hand combat specialist to learn how to handle the Wolverine claws.
The control stick that Cyclops uses to pilot the X-Men jet is a CH brand "Flightstick Pro" computer joystick.
Bryan Singer had one of his stunt men, Scott Leva, dress in a Spider-Man suit and confront actors James Marsden (Cyclops), Famke Janssen (Jean Grey), and Halle Berry (Storm) on set one day as a joke. Leva had actually dressed up in an identical Spider-Man costume once before for Marvel Comics in 1985 for the cover of "The Amazing Spider-Man" comic book, issue #262. In the outtake, Spider-Man realizes that he`s in the wrong movie, backs off and runs away, with Cyclops chasing after him shortly after. This can be seen as an "Easter Egg" on the first DVD edition of the movie, but not the "X-Men 1.5" DVD.
Despite being nearly 6 feet tall, James Marsden had to wear platform shoes so that he would appear taller than Hugh Jackman (6`2").
After knocking Storm down an elevator shaft, Toad (Ray Park) kicks away the bar that was holding the elevator doors open, grabs the bar, spins it over his head and then holds it in an attack posture in the same way he does with the double-ended lightsaber as Darth Maul in Star Wars: Episode I - The Phantom Menace (1999).
When Wolverine first explores the school he`s wearing black pants, no shirt or shoes, and is confronted by mirrors. This echoes Bruce Lee`s appearance in Enter the Dragon (1973).
Many of the X-Men from the comics who don`t have major roles in the film appear as minor characters in the school. Among them are: Jubilee, the Asian-American girl wearing a yellow jacket, hoop earrings with sunglasses above her forehead; Shadowcat, also known as Kitty Pryde; Colossus; Iceman, aka Bobby Drake, and Pyro.
George Buza, the trucker, portrayed the voice of Beast in the "X-Men" (1992) animated series.
# # Ian McKellen`s character, Magneto, is a Jew who survived the Holocaust. In Apt Pupil (1998), also directed by Bryan Singer McKellen portrays a Nazi who committed Holocaust atrocities.
# # When Wolverine complains about their outfits, Cyclops asks him if he`d prefer yellow spandex. This in-joke refers to the fact that the X-Men`s costumes in the comics are predominantly yellow spandex. Incidentally, after the sucess of this movie, the costume designs of the comics were changed to a "black leather" design similar to the one`s worn in the film.
After a defeated Storm re-enters the fight, Toad complains, "Don`t you people ever die?" This is an in-joke since, in the comics, almost all of the characters featured have "died" at least once, then come back.
The character Kitty Pryde (the girl who walks through the wall) was originally named after a real-life girl X-Men artist John Byrne knew in Calgary, Canada. When the movie was released there, local media managed to track down the "real" Kitty Pryde.
Toad was originally a hunchback, but that was changed so as not to interfere with Ray Park`s martial arts abilities.
The sunglasses Cyclops wears are Oakley "X-Metals", more specifically, the "Juliet" style with Ruby lenses. In keeping with the mythos of the comic book character, Cyclops must wear lenses with some form of ruby protection to contain his optic blasts which are uncontrollable without them.
# # Cameo: [Stan Lee] X-Men creator and executive producer is a man near a hot dog stand on the beach when Senator Kelly comes out of the water.
Cameo: [David Hayter] The writer appears as one of the cops near the end.
The police officer stabbed by Sabertooth in front of the Statue of Liberty was played by D.B. Sweeney, who is a fan of the X-Men and had tried out for the part of Cyclops.
Michael Chabon was approached to write the script.
Senator Kelly`s line at the beginning of the movie about having a list of known mutants living in the United States is based on Senator Joseph McCarthy`s famous speech about having a list of known communists working in the State Department.
# # While the WGA credits approbation, several writers involved in writing the screenplay decided to not be credited, and `David Hayter` received sole credit. The writers who contributed uncredited are: Ed Solomon, Christopher McQuarrie, Joss Whedon, James Schamus & John Logan.
After the film was completed, the wheelchair that the character Professor Xavier used was sold in an auction to Patrick Stewart`s attorney, and then rented back by the production company for X2 (2003).
Wolverine`s line, "What do they call you, `Wheels?`" was an ad-lib by Hugh Jackman (the scripted line was, "What do they call you, Baldie?").
James Marsden turned down a role in Soul Survivors (2001), in order to take part in this movie.
# # A scene appears in a TV spot for the film, but does not appear in the movie, of an extended talk between Scott Summers (James Marsden) and Professor Xavier (Patrick Stewart) regarding Logan`s stay at the mansion. Scott tells the Professor "He`s not one of us. There`s no way he`s going to take orders." Xavier politely replies, "Give him an order worth following. He`ll take it." More of this extended scene appears in the official movie adaptation novels and books, but it was cut out of the final film to meet the allowed running time.
The bar scenes were shot in the same brewery as the concentration camp scenes.
The last scene shot in Canada as part of principal photography was the first scene in the movie - that of rain falling on mud in the concentration camp.
Neither Patrick Stewart nor Sir Ian McKellen know how to play chess.
Angela Bassett turned down the role of Storm, while Aaron Eckhart and Viggo Mortensen were both considered for the role of Wolverine
Jada Pinkett Smith was considered for the role of Storm
When the project was in development at Carolco pictures, Michael Biehn was the front runner for the role of Cyclops.
Sarah Michelle Gellar was considered for the role of Rogue
Bryan Singer wrote the duologue between Wolverine and Cyclops when Cyclops refers to `yellow spandex` specifically to have a dig at fans on the Internet who complained about the X-Men`s costumes.
# # In the Hamilton location (the train station scenes), the director, Bryan Singer, was mistaken for an onlooker, and was harassed by a policeman, not letting him join the production team for some moments.
In the bar scene, after the fight where Wolverine gains some money, the guy behind the man that accuses Wolverine of cheating is Malcolm Nefsky, the film`s best boy grip. Because of the way the scene was filmed, someone was needed to deliver the line, and he was called because no certified "extra" was nearby.
The last scenes to be shot were the ones where Senator Kelly (Bruce Davison) emerges from water (in Santa Monica, California). They were shot in early May, and the film was released on the last days of July.
Hugh Jackman got his testicles caught in his harness after a 6 foot jump off the set`s Statue of Liberty.
The Mansion used as the Xavier school, is the same one Billy and his family lived in in Billy Madison (1995)
# # Joss Whedon wrote a draft version of the script, but the suggestions he made to fix what he felt were fundamental problems with the film were not incorporated. Only two pieces of dialogue from his rewrite appeared in the final film. One is the exchange when Cyclops doesn`t know if Wolverine is an impostor ("Prove it!" "You`re a dick"); the other is Storm`s "Do you know what happens when a toad gets hit by lightning? The same thing that happens to everything else." which he imagined as a lighthearted, offhand line.
Numerous actors were considered for the role of Wolverine. Bryan Singer talked to Mel Gibson, `Russell Crowe (I)`, Viggo Mortensen and Edward Norton, while Fox were interested in Keanu Reeves.
During a scene with Rogue, it is possible to see Bobby "Iceman" Drake`s breath even though it seems to be midsummer (an after effect of his ice-powers?). Fans noticed this detail and credited to director Bryan Singer`s dedication to the story and the particulars of each character`s powers. However, it was a mistake and never noticed nor intended for the film (in fact, the Iceman character is being impersonated by Mystique at the time). The effect was intentionally added to the story of the movie`s sequel X2 (2003), however, when Iceman and Rogue share a kiss.
Senator Kelly calls his aide "Henry" several times and when he asks Magneto what he`s done with Henry Magneto replies "Mr. Gyrich has been dead for some time." In the cartoon and in the comics Henry Gyrich was a member of several United States national security agencies, and was responsible for quite a bit of misery in the X-Men`s lives, including causing Storm to lose her powers and ordering the creation of one of the many models of Sentinels.
The very first scene shot for the movie was the World Summit scene on Liberty Island where representatives from each country are greeted. Two of the guests (identified by Bryan Singer as king and queen of Poland) are played by Bryan Singer`s father and stepmother.
Hugh Jackman`s physique looks slightly different in different scenes because he was cast 1.5 months after principal photography had started and kept working out extensively while shooting continued.
Patrick Stewart was the very first mutant to be cast.