"'X-Men'? What is so special about these 'X-Men'?"
- Henry Gyrich, interrogating Gambit in "Slave Island"

A cartoon based on the Marvel comic book of the same name, aired on the "Fox Kids Network" from 1992 to 1997. Needless to say, for a children's cartoon to run for that many seasons is rare; and its success is probably responsible (at least in part) for the plethora of Marvel-based cartoons which appeared since then (e.g. Spider-Man and the short-lived Silver Surfer series).

The X-Men cartoon, by and large, took a lot of its plots from the comic, but altered them either to make it fit into a 30-minute show, or for content, or for other reasons. For instance, there are versions of the Phoenix and Dark Phoenix sagas in the cartoon; but unlike in the comics (where Phoenix is some weird alien clone of Jean Grey), in the cartoon, Phoenix is an entity of pure energy that possesses Jean Grey. Likewise, the cartoon has its own versions of the Days of Future Past, Age of Apocalypse, and Phalanx Covenant storylines, among others. As children's shows go, X-Men was pretty well written - hardly Shakespeare, but infinitely more intelligent than, say, the Power Rangers (with the possible exception of the fifth season, which is noticably dumbed-down in spots).

Like the comic, the X-Men cartoon frequently deals with themes of racism and prejudice in general (though they carefully avoid the subject of homophobia, even though Northstar guest-stars in one episode). One episode in particular, "Beauty and the Beast", is an excellent example of this; in it, Beast is torn by his love for a (human) patient, the revealing of which provokes her bigoted father (and leads the anti-mutant Friends of Humanity to kidnap her).

"All right, you egg-sucking piece of gutter trash! You always liked pushin' around people smaller'n you. Well, I'M smaller! TRY PUSHIN' ME! "
- Wolverine, just before fighting Sabretooth in "Deadly Reunions"

Heroes

(For obvious reasons, the info here deals with the cartoon versions of these characters, who (in some ways) are different than their comicbook versions. Furthermore, I'm trying to give background without giving spoilers for the show - for instance, you'll notice the info on Jean Grey does not include the Phoenix Saga, even though it occurs in the cartoon.)

Codename: Professor X
Real Name: Charles Xavier
Powers: Xavier is the most powerful mutant telepath on the face of the Earth (though he was briefly superseded by Phoenix).
Background: Born into a wealthy family in the early 20th century, Charles was prone to powerful headaches in which he claimed to "see" things. These were the first manifestations of his mutant powers. Charles' father died very early on, and his mother became very ill during his early adolescence. She became involved with her physician, Dr. Marko, and eventually married him. Marko had a son from a previous marriage, Cain - who would become the Juggernaut. Later, Xavier became a doctor, and helped victims of an ongoing war. (It's never said what war this is, though in the comics, Xavier was drafted into the Korean War.) While there, he met another doctor, Magnus, who had the power to control electromagnetic fields. When enemy soldiers raided the hospital and took patients prisoner, Magnus and Xavier used their powers to rescue the hostages, revealing for the first time to anyone that they were mutants. While Magnus (who would later be Magneto) believed humankind would never accept mutants, Xavier was more optimistic, and in that spirit created his "school for the gifted" and the X-Men. Xavier usually stays behind on combat missions, though on a few occasions, his intervention has meant the difference between victory and destruction for the X-Men.

Codename: Cyclops
Real Name: Scott Summers
Powers: Can fire powerful laser-like rays from his eyes. Only eyewear made of ruby quartz keeps this power in check.
Background: When the Summers' private plane was attacked by a Sh'iar battlecruiser, the young couple heroically gave the only parachute to their young son, Scott, and tied his younger brother Alex to him. The two were sent to different orphanages; Scott spent the rest of his childhood under the care of Dr. Taylor Prescott, and then was taken in by Xavier as one of his first pupils. Cyclops long-time girlfriend is fellow student and later X-Woman, Jean Grey. He is field commander among the X-Men; only Xavier can supersede his orders.

Codename: Storm
Real Name: Ororo Munroe
Powers: Flight; Control and spontaneous creation of weather phenomena.
Background: Orphaned on the streets of Cairo; as a child, she was a pickpocket for the Shadow King. An accident from her youth which trapped her under the rubble of a building has caused her to develop claustrophobia as an adult, and this is referenced to several times throughout the series. Storm, through an odd sequence of events, is also godmother to an adolescent Kenyan boy named Mishnari; a mutant with the ability to run at great speeds (much like Quicksilver). She is second-in-command of the X-Men.

Codename: Jean Grey1
Real Name: Jean Grey (Duh.)
Powers: Strong telepath, also possesses some telekinetic ability
Background: Was one of the first students of Xavier's School for Gifted Children. Cyclops is Jean Grey's long-time boyfriend and fellow X-Man (or X-Person, if you want to be politically correct). She often stays behind on combat missions.2 1: Okay, it's not really a codename. But she doesn't have one in the cartoon. So there.
2:Okay, there's not a lot of info here. They never really delved into her past on the cartoon, and I don't want to contradict myself by putting in stuff from the comic.


Codename: Beast
Real Name: Henry "Hank" McCoy
Powers: Possesses superhuman strength and agility.
Background: Henry McCoy started out normal enough. As he progressed through adolescence, however, his arms and legs became progressively larger and heavily-muscled, his began growing fangs, claws and blue fur. (The cartoon contradicts itself here; that explanation was proffered in the episode "Beauty and the Beast", but later they used an explanation more in keeping with the origins of his "bestial" appearance - that it was caused by an experiment he conducted to try to rid himself of his mutation.) He was recruited by Xavier and (together with Cyclops, Jean Grey, Iceman, and Angel) formed the original X-Men. Besides his more obvious mutant abilities, it's possible that his extremely high intelligence is a result of mutation; besides holding a doctorate in biochemistry, Beast appears to be an expert in literature, medicine, and most of the sciences.

Codename: Wolverine
Real Name: Logan
Powers: Possesses enhanced senses and the ability to heal very quickly; skeleton and claws plated with adamantium.
Background: Much of Wolverine's past is a mystery, even to himself. Logan himself has no idea where he came from, who his parents were, or how old he is. His earliest memories involve working for Canadian intelligence during World War II; at one point going up against the Red Skull. Later, he was captured and made part of the Weapon X project, where various neurological experiments were performed on him, and ultimately he was subjected to a process that infused adamantium into his bones. After he escaped from Weapon X, he joined the Canadian state-supported superhero team Alpha Flight; but later left to find Xavier in the hopes that the Professor could help him control his bloodlust and help him piece together his past.

Codename: Rogue
Real Name: Unknown
Powers:Possesses superhuman strength, the ability to fly unaided, and the ability to borrow or steal life energy (and mutant powers) from others. Background: Rogue was born and raised in the Deep South (we never find out exactly where). The method by which she discovered her energy-stealing powers were unfortunate, to say the least; they first manifested in her first kiss - the boy in question was put into a coma for three weeks. Her family disowned her, and Rogue wandered around until she was found by Mystique, who made her part of her "family" of mutants. Mystique tricked Rogue into using her powers against Ms. Marvel, the resulting battle left Rogue with her powers - and her mind. She went to Xavier for help, and he used his telepathic powers to block Carol Danvers' mind from interacting with Rogue's. She has been a member of the X-Men ever since.

Codename: Gambit
Real Name: Remy LeBeau
Powers: Ability to make objects explode using their kinetic energy.
Background: Gambit lived in the swamps of Louisiana as a member of the Thieves' Guild. This is pretty much all that is known about him; Gambit is, as a rule, a very secretive man. (He also has one of the most nonsensical mutant powers ever conceived.)

Codename: Jubilee
Real Name: Jubilation Lee
Powers: Pyrokinetic; can create explosive bolts of plasma.
Background: Orphaned as a child, her adoptive parents became concerned (to put it mildly) when everything electronic that she touched began exploding. Unsure what to do, they registered her with Mutant Protection Agency - which sent a couple Sentinels after her. After Storm, Rogue and Gambit rescued her from the Sentinels, she became a permanent member of the X-men; however, due to her young age, she often is not allowed to enter combat situations. It has been suggested that Jubilee is much more powerful than one would suspect, but that they have been kept limited by mental blocks. There does seem to be some evidence of this; in the cartoon, her attacks are often more powerful when she's angry.

"Fools! You bleat for the future like a herd of sheep. I'll GIVE you your future - RIGHT NOW!"
- Apocalypse in "Come the Apocalypse"

Villians

Codename: Magneto
Real Name: Magnus
Powers: Can manipulate electromagnetic fields and magnetic metals to a very great degree.
Background: War has left Magnus a bitter man, and his view of the future is much more cynical that that of Charles Xavier. He believes that a war between humans and mutants is inevitable, and his goal is to strike first in order to weaken humanity as much as possible. He will do anything to achieve this goal - even kill the best friend he ever had.

Codename: Apocalypse
Real Name: En Sabah Nur
Powers: Shapeshifting to apparently-limitless proportions and superhuman strength; appears to be functionally invincible and immortal.
Background: Born to Egyptian royalty 5000 years ago, Apocalypse is one of the few mutants to emerge before the 20th century. He believes it is his destiny to destroy humankind and weed out "inferior" mutants, to create the perfect civilization, and his powers (and immortality) make it seem that he may eventually achieve his goal. It has been posited by some that he is the true Personification of Evil, though he does not see himself this way: "Evil? I am not malevolent; I simply am." ("Beyond Good and Evil, Part I")

Codename: Juggernaut
Real Name: Cain Marko
Powers: Possesses superhuman strength and is completely invincible.
Background: Cain Marko is Charles Xavier's stepbrother, and he holds one mountain of a grudge against him; Cain believes Charles was to blame for his father's abuse of him. One day Cain stumbled across the legendary Cave of Cyttorak (what he was doing there is not explained). Reciting the words on an ancient tablet while holding the "Ruby of Cyttorak", Cain was transformed into a "living juggernaut". Not only is he superstrong, but nothing seems to be able to kill him. Physical attacks, at best, slow him down; and he doesn't need to eat, drink, sleep, or even breathe. His only vulnerability is his mind, and even that is protected by his suit's helmet.

Codename: Mr. Sinister
Real Name: Nathaniel Essex
Powers: Superhuman healing ability, can also fire laser-like beams from his hands.
Background: After reading Darwin's Origin of the Species, Essex became obsessed with the concept of mutation. He was convinced that Darwin was only half-right; while admitting the existence of slow natural selection, he also believed that evolution could make great leaps in a single generation (acting on the erroneous belief that evolution is a process of progressive complexity). He was laughed out of the Royal Academy of Science for his theories and his rumoredly "sinister" experiments on human subjects. Studying various "freaks" he had had taken to him, he devised a serum that mutated his own genes. Besides turning his eyes red and his skin pure white, it gave him new, inhuman abilities. With these abilities, he vowed to show the world just how "sinister" he could be.

Codename: Sabretooth
Real Name: Graydon Creed Sr.
Powers: Superhuman strength, senses and healing ability, possesses fangs and claws. Background: Like Wolverine, Sabretooth was part of the Weapon X program. Frequently beaten by his father for his feral appearance, and subsequently experiencing a lifetime of bigotry on the part of "normal" humans, Sabretooth became a hardened, cold-blooded killer. He is in the employ of Magneto.

Codename: The Sentinels
Real Name: N/A
Powers: Each Sentinel is about 50 feet tall, can fly, shoot lasers, use tentacles to attack targets, and emit sleeping gas.
Background: Created by Dr. Bolivar Trask, the Sentinels are huge robots that exist for one purpose: to apprehend or destroy all mutants. They are created and programmed by Mastermold, an even bigger robot.

Fun Facts

  • Besides voicing their respective characters in various video games, many of the voice actors in X-Men were given roles in the various other Marvel cartoons, especially Silver Surfer and The Avengers. George Buza, the voice of Beast, played a small role as a trucker in the first X-Men movie.
  • Director Dan Hennessey did the voice for the role of the mutate Ruckus (who is essentially a pink-haired Banshee who can't fly).
  • There are at least two 'easter eggs' referencing producer Joseph Calamari. The first is in the season two episode, "Mojovision": Cyclops and Jean Grey go to an electronics store and the clerk's name badge has the word "Calamari" on it. The other is from the season five premiere, "Phalanx Covenant (Part 1)": Right at the beginning, a fake Sabretooth rips open the side of a truck and jumps out. The truck has the words "Joe's Calamari" on the side.
  • The entire cast of X-Men was flown to Los Angeles (from their studio in Canada) to voice their characters on two episodes of the Spider-Man cartoon that was also aired by FOX at the time, making those episodes rather expensive.
    Sources:
    http://www.tvtome.com/XMen/
    http://www.tvtome.com/tvtome/servlet/EpisodeGuideSummary/showid-2439/season-2
    http://www.imdb.com/title/tt0103584/
    And of course, personal experience watching the show.