Claremont is best known for his unprecedented tenure writing Marvel Comics' X-Men and Uncanny X-Men series.  During that time he was acclaimed for creating and developing strong female characters, as well as for introducing literary complexity to the story arcs.

"His papers will provide many clues, not only to the evolving way comic books are created and presented, but also how they are perceived, licensed, bought and sold in America and around the world," Louise Simonson, Claremont's editor and comics writer said.

"By developing more complex story structures and themes, he played a pivotal role in assembling the audience that enabled American comics to move to more mature and sophisticated storytelling, and the graphic novel,” Paul Levitz, former president and publisher of DC Comics said. “When scholars look back and understand this pivotal change in our popular culture, his papers will prove invaluable."

The plots for the first two X-Men films are based in great part on Claremont's stories, particularly his graphic novel God Loves, Man Kills.  In addition to his work for Marvel, Claremont has also written several notable creator-owned stories, including Sovereign Seven for DC Comics and the historical fantasies The Black Dragon and Marada, the She-Wolf.  He is known for his genre fiction as well, such as the High Frontier science-fiction series.