Since the announcement of DC's line-wide relaunch hit last week, readers have been wondering what exactly all of this means for the publisher and their comics. Titles, creators and even distribution methods are all up in the air in what's turning out to be a pretty huge shake-up. But for the stories, this is nothing new: DC's been retconning, revising and rebooting their universe for over 70 years. So today, as we all get ready for yet another all-new DCU, we're taking a look back at all the times nothing was ever the same again, from parallel worlds to punching continuity!1940: All-Star Comics #3 Creates The DC Universe

While most people rightly consider Action Comics #1 to be the cornerstone on which DC Comics was built -- and really, the rest of the super-hero genre as a whole -- the idea of a cohesive DC Universe wasn't brought to the forefront for a few years. Before this story, most DC super-heroes had existed completely independent of each other, but in All-Star Comics #3, for the first time, they were shown living in the same world, interacting with each other and forming a team that would set the tone for later groups.

It's also worth noting that all of this happened in what was technically an inter-company crossover. At the time, All-American Comics (publishers of the Flash, the Atom, Hawkman and Green Lantern) and National Comics (publishers of the Sandman, Spectre, Dr. Fate and Hourman) were separate companies, though both were marketing themselves by using the logo of another company -- Detective Comics Inc. -- which had recently introduced a fairly popular character called "The Batman" that some of you may be familiar with. It wasn't until 1946 that the companies officially merged as National Periodical Publications, better known (especially after officially changing its name in 1977) as DC Comics.

But the groundwork of the shared universe was laid here, especially with the imposition of a rule that mandated a rotating cast by booting out team members that were given their own series, making room for the inclusion of newer characters as they arrived, like Johnny Thunder and Wonder Woman. The more popular characters were still considered to be "Honorary Members," and it all led to building a world where all of National's super-heroes could interact with each other.

1956: The Silver Age Flash and The First Retcon

While Superman and Batman remained popular, the other characters of the Justice Society -- and super-heroes as a genre -- had waned in popularity by the early '50s. They got another chance in 1956, however, and while a great deal of the credit has to go to the establishment of the Comics Code Authority and its goal of cutting the wildly popular crime and horror genres off at the knees, the rebooting of Golden Age heroes into new, updated counterparts was a pretty huge factor as well.

It started in Showcase #4, which not only introduced a new Flash, but explicitly referred to the Golden Age version as being a comic book character within the comic itself.

With this, the previous Flash -- and by extension, all of his Golden Age teammates in the Justice Society -- were retconned into being fictional characters even within the comics in which they'd originally appeared. And while it's often remembered as a huge gap between the two groups of stories, Barry Allen's first appearance was only five years after Jay Garrick's last.

Either way, it took off, and the rebooted Flash was soon joined by new versions of Green Lantern, the Atom and of course Hawkman, paving the way for the most confusing series of reboots and revisions in comic book history.

1961 - 1963: The Creation of the Multiverse

If there's one thing we should all know about the comics industry at this point, it's that it never lets anything go away forever. And that's not a new trend, either. The historic "Flash of Two Worlds" story in 1961's Flash #123 finally reintroduced the Golden Age Flash to the regular DC Universe, establishing that he was a super-hero on an alternate dimension.

This of course led to the eventual return of the entire Justice Society in Justice League of America #21, and the idea that the super-heroes being published monthly existed on just one of several Earths in an entire multiverse of infinite possibilities. Outside of the actual text, this also gave DC a convenient way to slot in characters and companies that they'd absorbed over the years. In the same way that National, Detective and All-American had united to form the core universe, characters like Captain Marvel (acquired in a lawsuit against Fawcett Publications), Plastic Man, Blackhawk and the Freedom Fighters (picked up from Quality in the '50s), and even later additions like Blue Beetle and the Question (acquired from Charlton in 1983) were given an easy way to blend into the fabric of DC's universe. In effect, they'd stumbled on a way to make every single comic book ever published a potential part of their multiverse, a fact that Alan Moore acknowledged when he coined the term "Earth-616" as the "official" name of the Marvel universe during his run on Captain Britain.

It's also interesting that with Showcase #4's portrayal of the Golden Age heroes as only existing in comic books on Earth-1, DC had also paved the way for the idea of showing the real world as part of their multiverse, an idea they capitalized on in the creation of Earth-Prime, a fictionalized version of the real world that not only crossed over with the super-heroes being created by writers and artists who lived in that world, but was also destroyed by nuclear war in a literalized example of Cold War fears.

It might sound confusing, but it is and it isn't at the same time. The actual specifics that comic book readers would pride themselves on memorizing ("No, the Earth-X where the Freedom Fighters live, not the Earth-X from that one issue of Jimmy Olsen!") can be pretty difficult to keep straight, but the basic idea that there are different worlds with different heroes that can cross over and interact with each other is a pretty simple one that produced some of DC's most memorable stories from the era. It even allowed them to tell stories of Superman and Batman growing old or getting married without tampering with the more popular (and profitable) status quo.

Which isn't to say that it wasn't complicated, either. There were stories that reveled in the complexities inherent in the book, like the migration of Red Tornado and Black Canary from Earth-2 to Earth-1.

1986: Crisis on Infinite Earths Destroys The Multiverse (For a While)

By the 1980s, popular perception of DC's multiverse had shifted from being a storytelling tool that allowed for infinite possibilities to an overly complex barrier that kept readers from embracing their stories. When contrasted with the Marvel Universe, which had reincorporated Golden Age characters like Captain America and the Sub-Mariner directly into their core universe, the multiverse idea seemed more awkward and unwieldy. Throw in continuity errors -- an inevitability when you've got 50 years of stories created by hundreds of different people, all of whom are adding something new to the universe -- and DC started to look like something that needed to be fixed.

Thus, Crisis on Infinite Earths, the first, biggest and most successful exercise in continuity as storytelling. The tagline for the series was "Worlds will live, worlds will die and nothing will ever be the same," and for better or for worse, it delivered on all of those. It was quite simply the biggest possible story they could possibly tell -- the entirety of comic books was endangered, and not everyone made it out.

On one level, this thing's as big a mess as anything, with a plot that at one point is about a bunch of tuning forks that are quickly forgotten in favor of housekeeping, but the impact it had was huge, both within the story and metatextually. The characters of the multiverse were folded into one unified world, leading to characters like Blue Beetle and the Question becoming mainstays of the DC Universe, and the recasting of the Justice Society as the forerunners of the "modern" heroic characters. It was a fresh start for almost everyone -- including Wonder Woman, who was taken out of circulation for a while before a major relaunch -- and even characters like Batman who were pretty much the same as they were in 1986 as they had been for the past ten years were given an opportunity to jettison more awkward and contradictory elements of their histories (Bruce Wayne being raised by his Uncle Philip and Joe Chill's mom, for instance) in favor of more streamlined origins like Year One.

Most important, though, were the changes to Superman. Crisis was, for all intents and purposes, the end of the Superman readers had known for fifty years, with a fresh start that -- and stop me if any of this starts to sound familiar -- saw the Superman title relaunching with a new #1. Along the way, it eliminated supporting cast members like Supergirl, changed his origin and his powers, and did away with the entire concept of Superboy, all in an effort to update and simplify him.

That should fix everything, right?

1987: Oh, Right. The Legion.

As it turns out, when you get rid of Superboy, you make things awkward for the Legion of Super-Heroes, which was at the time one of DC's most popular franchises. Not only was the Legion specifically based on teaming up with Superboy, but the team had only recently (1982) been through the acclaimed "Great Darkness Saga," which featured both Superboy and Supergirl -- now nonexistant -- in critical roles.

So rather than rebooting the Legion and derailing its momentum, the solution was to base the team on a pocket universe that was created by the Time Trapper that did have a Superboy, Supergirl, Krypto, and so on. In essence, there was a small piece of the Silver Age that made it through Crisis, but only in regards to one specific group.

Surely that wouldn't create any problems.

1994: Zero Hour Fixes It All Again

Less than ten years after Crisis on Infinite Earths, the DC Universe still had a ton of continuity problems, which can basically be boiled down to four words: Hawkman and Donna Troy.

Okay, okay, it wasn't all those two. The previously addressed problems with the Legion had only gotten more confusing when a batch of clones of their happy-go-lucky Silver Age selves were discovered, leading to two separate Legion books about different verisons of the same characters operating at the same time. There were also problems with stories that had been published after Crisis that DC wanted to quitely get rid of, like "Batman: Year Two," a truly hilarious bit of insanity in which Batman teamed up with Joe Chill and tried to kill him using the same gun that killed his parents, which he'd kept in a drawer for thirty years. And then there was the Justice Society, which unlike the rest of the universe was tied explicitly to a fixed point in time (World War II) which required an explanation as to just why they were still running around doing super-heroics forty years later, especially when they'd been supplanted by younger characters.

The solution was another Crisis called Zero Hour, a "Crisis In Time" that would help smooth things over. As a result, the JSA was de-aged and the Legion was given a fresh start that recast them as teenagers inspired by all the heroics of the DC Universe, rather than just Superboy.

Hawkman still didn't make any sense, though.

1999: The Kingdom Creates Hypertime

With continuity errors and a desire to use plot elements that had been discarded by Crisis poking more holes into their "streamlined" universe than a road sign outside a Texas gun shop, it fell to writer Mark Waid to finally provide an explanation that could cover everything, and the DC Universe was introduced to the concept of Hypertime.

Much like the original multiverse idea, Hypertime was a solution that relied on the simple fact that this was a fictional universe, and took the stance that everything, from the current mainline DC Universe to the wild weirdness of the Silver Age to stuff like the Superman and Batman movies, had all happened in some permutation of the universe. Time was like a river, with an infinite number of branches spinning off to do their own thing, sometimes ending in a finite story and sometimes rejoining the main branch if a creator wanted to include an element in a mainline story.

This was a pretty mature solution that provided a simple in-story way to explain errors and changes by treating the subject matter like what it actually is: a story. So of course, it was almost completely ignored by DC editorial, with Dan DiDio completely rejecting it six years later in a public statement.

One would think that the announcement that they were abandoning a solution to continuity errors meant that everything was fixed forever.

2003: Superman: Birthright Gives The Man of Steel Another Origin

Well, apparently some things could still use some fixing, because in 2003, Mark Waid and Leinil Yu's Birthright supplanted John Byrne's Man of Steel as the official origin story for Superman.

While not quite the hard reboot that Man of Steel was, Birthright was certainly a big adjustment, returning to the idea that Clark Kent and Lex Luthor had known each other during their childhood in Smallville, mirroring the Smallville television series. With that in place, it would seem that Superman had been sorted out for at least the rest of the decade.

2005-2010: The Legion Gets Threebooted, Then Debooted, Then Triple-Booted

Speaking of Mark Waid and reboots, the 2005 "Threeboot" of The Legion of Super-Heroes saw Waid taking a second crack at rebuilding the franchise after being one of the writers who oversaw the 1994 version. To a lot of fans (including me), this seemed like a completely unnecessary revision, especially given how critically acclaimed its predecessor had been in recent years under the writing team of Dan Abnett and Andy Lanning. But with those guys moving on to Marvel and their tenure on the cosmic titles, it seems there was someone who thought it was a good time for a fresh start.

In this one, the updated codenames of the Zero Hour Legion (Livewire, Apparition, Triad and so on) were rolled back to their original versions (Lightning Lad, Phantom Girl, Triplicate Girl and so forth) and as a nod to the Silver Age Flash's origin story, they took their inspiration from comic books that had survived from the 20th century. An interesting idea, but not one that was long for this world.

Not to get ahead of myself here, but the Threeboot Legion ran into some trouble when the absolutely atrocious 2007 "Lightning Saga" story in Justice League and Justice Society became the next in DC's all-consuming policy of regressive storytelling by reintroducing an idealized version of the original Legion, last seen in the late '80s. And according to interviews, this was done without the knowledge of Waid, who was still writing Legion of Super-Heroes at the time.

The whole mess took three years to sort out, and ended in 2007 with Final Crisis: Legion of Three Worlds, where it was revealed that three completely different Legions -- four if you count the one from their eponymous cartoon -- were all operating in different branches of the time stream at the same time, and all of them could interact with the regular DCU timeline, although the primary one featured in the comics would be the one old people liked. Because that was way simpler than parallel worlds, right?

2006: Infinite Crisis Makes New Earth

But let's backtrack a second to 2006 and Infinite Crisis, a series that was ostensibly meant to be a 20th Anniversary follow-up to Crisis on Infinite Earths that instead became a truly ludicrous pastiche. The main storyline began with Superboy-Prime literally punching continuity in order to "fix" things and ended with the Golden Age Superman getting bloodily beaten to death. It was charming, I assure you.

Somewhere along the way -- probably around the time a lawsuit from Jerry Siegel's heirs led to Superboy also being beaten to death -- the series mentioned the creation of "New Earth," which was pretty much an excuse to return elements that had been discarded from continuity 20 years before, like Superboy and Batman once again finding the identity of his parents' killer.

Finally, everything had been straightened out for good.

2007: 52, Because Really "Infinite" Earths Were WAY Too Many

...except that it actually hadn't. In 52, the year-long follow-up to Infinite Crisis, the multiverse came back, except that instead of being an infinite number of parallel worlds, the number of Earths was capped (in a seemingly completely arbitrary move) at 52. If memory serves, it was less than a month after this revelation that DC began contradicting itself as to which Earth was which.

Either way, the move put the emphasis back on the core DC Universe (formerly "New Earth," now Earth-1 according to some sources, Earth-0 according to others) with the idea that the 52 worlds were arranged in a cosmic interdimensional inverted pyramid, with (New)Earth-(1 or 0) at the bottom as the lynchpin on which the others rested. Oh, and the other worlds also all had their own multiple timelines.

Finally. A simple slolution that anyone would be able to grasp. So much less complex than Hypertime.

2009: Okay, This Time It's REALLY Superman's Origin

At this point, so much had changed that DC was forced to discard the origin for Superman that they'd released only six years before by chucking out Birthright and replacing it with Secret Origin. An updated throwback to the Silver Age, this was the book that fully restored a young Clark Kent's career as Superboy and his childhood interactions with the Legion of Super-Heroes, as well as returning Lex Luthor to Smallville.

At long last, Superman had been given a definitive origin story that would stand the test of time.

2010: No Seriously, THIS Is Superman's Origin

...or at least until the very next year, when DC released an even more updated version of Superman's origin designed to appeal to the bookstore market with the inexplicably named Superman: Earth One.

Standing as one of the only stories J. Michael Straczynski would actually finish after being hired to write, this one focused on Clark Kent's arrival into Metropolis with a story where Superman helps exactly one person over the course of an entire graphic novel, and where Krypton was blown up by a guy named Tyrell who speaks in dialogue that's trying so hard to look badass that it's amazing the actual letters aren't wearing Ed Hardy shirts.

At this time, it's unknown as to whether or not this is going to be incorporated into the mainstream universe as Superman's origin, or if it's just going to be a story that takes place on a parallel Earth where newspaper editor Perry White doesn't know what "active voice" means.

2011: Flashpoint Throws Out The Bathwater, Baby Reported Missing

And that brings us up to the reboot du jour, Flashpoint, which promises to muck around with the DC Universe on an unprecedented scale that will lead to the entire line getting a reboot and every single DCU title being relaunched with a new first issue.

What exactly this means for the universe itself remains to be seen, but based on what we've seen, I imagine we're probably going to get the fourth Superman origin story in less than ten years, and I wouldn't hold out hope for the Legion to get out of things unscathed either.

But I think we can all take comfort in the two pieces of consistency that have seen readers through all the other reboots. First, the fact that the stories you love will always be there, and while the new changes might result in something better, a bad change can never take away what you've already got. Second: Hawkman and Donna Troy still won't make any sense.

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