The X-Men books have long been trendsetters for Marvel. While the book wasn't among the more popular Silver Age Marvel books, X-Men would more than make up for it in the years to come. The X-Men and their books became Marvel's most popular. Their characters supplanted teams like the Avengers and the Fantastic Four as Marvel's biggest. For years, the X-Men were Marvel in the eyes of audiences.

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X-Men books have done all kinds of things that no other Marvel comic has. The X-Men have set the industry standard in all of kinds of ways, standing out stronger than just about any Marvel franchise out there.

10 They Survived Marvel Actively Trying To Destroy Them More Than Once

No More Mutants And Inhumans Vs X-Men

Marvel has had a complicated relationship with the X-Men in the 21st century. In order to stave off bankruptcy in the '90s, Marvel had to sell the film rights of the franchise away. This led Marvel to try make the books less popular, first with House Of M depowering mutants and pushing them into a smaller corner of the Marvel Universe, often leaving them out of company wide events. Things came to a head with Marvel trying to push the Inhumans in place of the X-Men. Marvel has tried to erode the popularity of the X-Men several times and yet they've survived every time.

9 The Age Of Apocalypse Was An Unprecedented First

Heroes from the Age of Apocalypse arc pose heroically against a blue background

Alternate universe storylines in comics weren't a new thing in 1994, but Marvel was about to do something with the X-Men books that they'd never done before or since with their franchises. The Age Of Apocalypse wasn't like any other alternate universe story; Marvel renamed each X-Men book and set them completely in this new universe.

This was the first time Marvel did this, putting all of its current X-Men stories on pause to tell an alternate universe tale. While they've tried to re-catch lightning in a bottle twice with Age Of X and Age Of X-Man, they didn't put the entire X-Men line on hold for these stories and they've never done anything like it in any other comic.

8 Chris Claremont Wrote X-Men Books For Longer Than Any Other Writer On A Marvel Comic

Chris Claremont's X-Men documentary

Marvel has had some long tenured writers, but none of them hold a candle to Uncanny X-Men wunderkind Chris Claremont. Claremont wrote Uncanny X-Men for seventeen years in his first stint on the book, from 1974 to 1991. He then wrote X-Men and Uncanny X-Men for another year in 2000 to 2001. He came back to Uncanny X-Men in 2004 for another two year run on that book.

RELATED: 8 X-Men Stories With Endings That Make No Sense

Over the years, Chris Claremont has altogether wrote twenty years of mainline X-Men books and that's not even counting books like X-Men Forever. No other Marvel book has ever had a writer that worked on them for as long as Chris Claremont did.

7 They've Killed Jean Grey Several Times

Jean Grey in her Hellfire Gala Outfit in Marvel Comics

This is sort of a technicality, but the X-Men books have killed Jean Grey several times, which is something no other Marvel series has done. Jean Grey is one of the X-Men's most important members and she's played a huge role in team's history. She's also has a reputation for dying and she's done it several times in the X-Men books.

Jean Grey's deaths have always been huge deals in the X-Men books and it's not something that other books really do. No other team book has killed off one of their founding characters and left her dead for as long as Marvel has with Jean Grey.

6 The Current X-Men Run Has Focused On The Darker Aspects Of Nation Building

Professor X graces the cover of Inferno #3.

Professor X isn't exactly the best character in the Marvel Universe, but his role in founding the nation of Krakoa has brought something completely new to the Marvel Universe. While Marvel is no stranger to having superheroes be world leaders, the Krakoa era is the first time that readers have gotten in on the ground floor of nation building.

Not only that, the X-Men books have often focused on the darker aspects of nation building, as mutants have had to do some rather extreme things to insure their power and standing in the world – including leaders like Professor X and Magneto lying and keeping secrets from their people while having X-Force commit war crimes to keep Krakoa safe.

5 They've Made Resurrecting Dead Characters A Plot Device

Professor X The Five Krakoa

House Of X/Powers Of X kicked off the Krakoa era and it did so by dropping all kinds of revelations on readers. One of the biggest was the Krakoan resurrection method. Resurrecting dead characters has always been a big part of comics, but the X-Men comics are the first ones to make it an actual plot device.

Resurrection and the X-Men have went hand in hand for years, so them coming up with a viable and useful method of resurrection was completely on brand. It was a huge surprise, though, and no other Marvel comic has ever done anything like it. It's changed the landscape of the mutant side of the Marvel Universe.

4 They've Taken Their Most Iconic Foe And Made Them An Integral Member Of The Team

Xavier Magneto Destiny Inferno

Magneto is the X-Men's most iconic villain and he's been through a lot of changes since the Silver Age. One of those changes was to make him less of a Stan Lee-written stereotype villain. This is another legacy of the Chris Claremont run, as Claremont fleshed out the villain and made him into a more well rounded character.

Magneto's complicated relationship with Professor X and the X-Men has made the character one of the franchise's most popular and he's now a member of the team. No other team book has ever taken their main villain and made them into a long term member of team.

3 They've Dealt With Genocide In A Way No Other Marvel Comic Has

Genosha New X-Men Grant Morrison

Mutants have been used as an allegory for racism of all kinds and the X-Men books have dealt with genocide in a way no other comics have. Genocide has happened in other comics before, but it was always rather impersonal and little more than a plot element – like "Ultron Unlimited" or Infinity Gauntlet. In X-Men books, the genocide is always more personal and has a major impact on things.

RELATED: Marvel: New X-Men Mutations Everyone Forgot About

The Genosha genocide changed the way the X-Men looked at the world and was one of the worst days in mutant history. It was more than a plot device to give a story stakes, but a terrible event that changed things forever.

2 The Only Marvel Ongoing Series Written By Grant Morrison Is New X-Men

New X-Men

Grant Morrison is one of comics' greatest writers, known for their amazing works at DC Comics. Morrison came to Marvel from 2000 to 2004. They worked on miniseries like Marvel Boy and Fantastic Four: 1234 for the Marvel Knights line before taking over X-Men and rechristening it New X-men.

New X-Men was a revelation, taking a new approach to the team that mixed the old with the new, something Morrison excelled at. Differences with Marvel editorial drove them away from the company in 2004 and the only ongoing they ever wrote was an X-Men book.

1 X-Men #1 Sold Eight Million Copies

Cyclops and Wolverine lead the X-Men against Magneto from Marvel Comics

X-Men #1, by writer Chris Claremont and artist Jim Lee, is the best selling comic of all time. The issue sold eight million copies in 1991, a number no other Marvel book reached before or since. X-Men #1 cemented the X-Men's hold on Marvel in the '90s and introduced the most popular X-Men roster of all time, the Blue Team.

Marvel comics have long been the best selling comics in the industry but none of them have ever even come close to selling as much as X-Men #1 did. Even the best selling modern Marvel comic doesn't sell as many copies in a year that X-Men #1 did. Even in this pop culture environment of superheroes being more popular than ever, it's doubtful any book will ever again.

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