X-Men

The X-Men are a fictional team of superheroes appearing in American comic books published by Marvel Comics. Created by artist/co-plotter Jack Kirby and writer/editor Stan Lee, the characters first appeared in The X-Men #1 (September 1963) and formed one of the most recognizable and successful franchises of Marvel Comics, appearing in numerous books, television shows, films, and video games.

In the Marvel Universe, mutants are humans who are born with natural superhuman abilities, and most normal humans fear and hate them. The X-Men are a paramilitary group of mutants that fights for peace and equality between normal humans and mutants. They are led by Charles Xavier, also known as Professor X, a powerful telepath. Professor X runs a school for mutant children out of his mansion in Westchester, New York, which secretly is also the headquarters of the X-Men. The X-Men's archenemy is Magneto, a mutant with magnetic abilities who leads a mutant supremacist group known as the Brotherhood of Mutants.

The series' creator and fans have suspected that Marvel Comics copied the basic concept of Doom Patrol from DC Comics to create the X-Men, which debuted a few months later, but other fans also speculate that they share similarities with another Marvel superhero team, the Fantastic Four.

Original members
Notation:
 * Characters in bold are members of the team as of the present time.
 * A slash (/) between names indicates codenames of one character in chronological order.
 * Characters listed are set in the Earth-616 continuity except when noted.