X-Men # 1 Jim Lee Connecting Cover 1991 NM-

X-Men # 1, published in October 1991, is the best-selling comic book of all time and features the newly formed Blue Team of X-Men in an action-packed confrontation with their archenemy, Magneto, and the debut of his followers, the Acolytes. The issue was co-written by Chris Claremont and Jim Lee, with art by Lee, and was a landmark publication that defined the look of the X-Men for the 1990s.

The Story: "Rubicon"

The issue's main story, titled "Rubicon," sets up the new status quo for the X-Men and features multiple plot threads:

Asteroid M and the Acolytes: A group of mutant refugees, including Fabian Cortez, steal a S.H.I.E.L.D. shuttle and flee to Asteroid M, which is now the base of operations for Magneto. Magneto, who had been attempting to live in isolation, is convinced by Cortez to make a stand for mutantkind, leading to the formation of his fanatical Acolytes.

The X-Men Divided: Back at the X-Mansion, the X-Men have formally split into two field teams to manage their expanding roster: Cyclops's Blue Team (Cyclops, Wolverine, Beast, Gambit, Rogue, and Psylocke) and Storm's Gold Team (operating primarily in the Uncanny X-Men title). The Blue Team is training in the Danger Room when they are alerted to Magneto's activities by Nick Fury.

Confrontation: The Blue Team confronts Magneto in the Atlantic Ocean, where he has raised a sunken Soviet nuclear submarine (Leningrad) and intends to use its nuclear arsenal as a deterrent against human aggression. A battle ensues, during which Rogue attempts to reason with Magneto due to their past connection, but she is shot down by a Russian fighter jet.

Escalation: Rogue crash-lands in Genosha and is attacked by the Acolytes, who want her to join them. The rest of the Blue Team arrives to help her, and Magneto appears to declare Asteroid M a haven for all mutants, setting the stage for future conflicts. A tearful Moira MacTaggert is revealed to have a dark secret regarding Magneto, hinting at a larger, underlying storyline.

X-Men # 1 (1991) is a major landmark for Marvel Comics, marking the first appearance of several key characters and the debut of the iconic 90s team rosters. 

Character and Team Debuts

• The Acolytes (Team): Magneto's new fanatical followers who believe in mutant superiority and seek refuge on Asteroid M.
• Fabian Cortez: The manipulative leader of the Acolytes who possesses the ability to overcharge or "boost" other mutants' powers.
• Other Acolytes: This issue also introduces members Anne-Marie Cortez, Chrome, Nance Winters, and Delgado.
• X-Men Blue & Gold Teams: While the individual members were existing characters, this issue formally established the Blue Team (led by Cyclops) and Gold Team (led by Storm).