X-Men:
* Uncanny X-Men #94-161 (1975-1982): This is widely considered his defining work. Claremont introduced beloved characters like Wolverine, Nightcrawler, Storm, and Colossus. He also fleshed out the existing cast, explored their individual struggles, and developed the concept of mutantkind as a persecuted minority.
* Excalibur (1988-1998): A spin-off series featuring characters like Captain Britain, Nightcrawler, and Meggan.
* The New Mutants (1983-1991): This series introduced a younger generation of mutants, including Cannonball, Sunspot, and Wolfsbane.
* X-Men: The Hidden Years (1985): A miniseries detailing the X-Men's early adventures.
* X-Men: God Loves, Man Kills (1982): A graphic novel that was highly praised for its mature themes and exploration of religious extremism.
Other Marvel Comics Work:
* Spider-Man (1979): Claremont wrote a few issues of the title, introducing the character of Black Cat.
* The Fantastic Four (1981): Claremont penned a run on the Fantastic Four, focusing on the Thing's struggles and the introduction of the villain Doom's daughter, Valeria.
Beyond Marvel:
* The Adventures of the Phantom (1990s): He wrote issues of this long-running pulp hero comic.
Claremont's work on X-Men was groundbreaking, influencing both comics and popular culture. His contributions to the series continue to be celebrated by fans and critics alike.