Marvel didn't invent the idea of a comic book Multiverse, or the idea of their most iconic characters re-imagined across an endless number of realities, parallel universes, and incredible 'What If?' alternatives. Of course, there's never any doubt which is the true, original Marvel Universe: found in the reality designated Earth-616.

Over the years, this bit of comic book trivia has migrated into the movies, planted as a winking Easter Egg for fans in the know. First having Thor: The Dark World theorize a '616 Universe,' later quietly confirming the washed-up Spider-Man is the original Peter Parker in Spider-Man: Into the Spider-Verse. But with Jake Gyllenhaal's Mysterio explicitly calling out 'Earth-616' and the MCU Multiverse, more fans than ever before will know the truth about Marvel's main reality. Which also means a new generation of people asking the same question: why is it called the 616 Universe, anyway?

We're here to explain this mystery, from its conflicted origins to the attitude Marvel's own writers have to the name, and why the '616' designation might not even be accurate anymore. One way or another, the truth is going to surprise you.

What '616' Really Means in Marvel's Multiverse

Marvel 616 Universe Captain Britain

The question of when and how Marvel's 'prime' reality earned the designation '616' is easy to answer, even if the motivations behind it have been the subject off disagreement. The term first appeared in the pages of The Daredevils #7 (1983), a UK comic series featuring multiple heroes, led by Marvel's own UK superhero Captain Britain. To keep a long story short, the Captain (Brian Braddock) gets caught up in an interdimensional court case over the destruction of a reality. Braddock soon finds he is just one of an endless number of parallel reality variations making up a larger Captain Britain Corps. To distinguish Brian from the others, he is referred to as "Captain Britain of Earth 616."

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The short story titled "Rough Justice" is credited to writer Alan Moore and artist Alan Davis, so it should be easy to find out who had the idea of assigning a number to Marvel's original reality. When Davis was credited for the assigning of the number, he claimed it was the work of prior Captain Britain writer Dave Thorpe. The number? Davis said it reflected Thorpe's cynical views on superhero stories, giving their universe a variation of The Mark of The Beast ('666'). However, since Thorpe is on the record as a fan of superhero comics, Alan Moore seems a simple candidate. The best explanation tied to the mind behind Watchmen and The Killing Joke is that the number is a random one--but intended to subvert the DC books at the time, which suggested their original universe was 'Earth-One' as opposed to a truly random example.

Marvel's Top Executives Actually Hate '616'

Marvel Comics Spider-Verse

The number of times that the term '616' has popped up in Marvel projects would lead the average viewer to assume the designation is a point of pride, or at least a sense of tradition now honored by Marvel editors, writers, and artists. Ironically, it seems that the justification for Moore selecting 'Earth 616' came to embody the opposite message of what Marvel Comics would later wish. To Moore, suggesting there was nothing special about THIS Marvel Universe had meaning. But to the later editors charged with making Marvel stories feel important, fans can probably see the problem.

After Brian Michael Bendis struck massive success with Ultimate Spider-Man, re-imagining the hero in an alternate reality--one which would eventually come to be called the Ultimate Universe--the possibilities and 'What If?'s seemed limitless. It was in that window of mid-to-late 2000s that Marvel Editor Tom Brevoort spoke publicly about his dislike for the '616' number. When asked his opinion by Newsarama, Marvel Editor in chief Joe Quesada didn't mince words either:

I never use it, I hate the term pure and simple and agree with Tom’s assessment of it. I can’t remember ever hearing it in the office and only really see it used online for the most part... I think the term really came into vogue when the Ultimate Universe came into prominence, but in my world, the language and distinctions are simple, there is the Marvel Universe and the Ultimate Universe. Anything other than that reeks of all that DC Earth 1, Earth 2, Earth Prime stuff which I’ve never really taken to, but then again, I got into DC when they got rid of all that stuff so it was from and for a different era than my own.

Technically, Marvel's Universe Isn't '616' Anymore

The point being made by Quesada makes sense to regular readers, since the only two ongoing and constant realities in Marvel's catalogue really are the main Marvel one, and the Ultimate variation. But just as DC's expanding Multiverse was culled and folded together by the Crisis on Infinite Earths, Jonathan Hickman and Esad Ribic set out to the do the same at Marvel with Secret Wars. The 2015 event combined realities and heroes onto one massive Battleworld... before destroying most, and disappearing Reed and Sue of the Fantastic Four along with them.

Of course, it only seemed like the Fantastic Four were killed. The final issue, Secret Wars #9 revealed that while the rest of the Multiverse had been erased, the Richards' had the power (along with their kids) to recreate the Multiverse as it had been before. Which, as Brevoort explained to CBR at the time, meant the '616' designation was actually no longer accurate:

It's effectively a new multiverse. The biggest and most important thing here that nobody in the world will like, and that I'm the only one that keeps poking at, is the fact that the Marvel Universe is no longer the 616. I don't know if by the end of "Secret Wars" #9 there are 616 universes yet. There will be an infinite number of them. Realities that we've known and new ones that we've never visited before are being constantly created, and then mapped and explored by Reed and his family. They started by restoring the Marvel Universe. So really, it's now the Prime Universe.

So there you have it, folks! The explanation for Marvel's superheroes residing in The 616 Universe, and the perfectly clear reason why the title isn't even accurate. And despite the editors (and at one time the writers) disliking the designation completely... there's just no stopping it.

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Source: Newsarama, John Reppion, CBR