The Golden Age
In the 1940s, American comic books were dominated by colorful costumed super-heroes, almost all of them tracing their roots back to Superman and Batman. There were dozens of different heroes, some popular, some appearing only once or twice before vanishing forever. By the early 1950s, that horde was nearly extinct. At DC Comics, the only survivors that retained their own comic book titles by 1952 were Superman (and his younger self, Superboy), Batman, and Wonder Woman, along with a handful of others (Aquaman, Green Arrow, Robotman, the Vigilante, et al) who survived as back-up features. Publishers instead turned to westerns, crime comics, war comics, and science fiction — any genre to fill the void.
The Silver Age and Earth-Two
In 1956, DC Comics editor Julius Schwartz decided to try out a new character in the fourth issue of the ongoing try-out series Showcase Comics: a modernized version of the Flash, one of DC’s more popular heroes of the forties. The new Flash, like the original, had the power to move at super-speeds, but he was otherwise an entirely new character, with a different costume and a different origin as police scientist Barry Allen. His adventures were a success and before long he graduated to his own book, reviving the old Flash Comics numbering.
Realizing that these revamped super-heroes could be hits with modern readers, Schwartz tried another Forties stalwart, Green Lantern, whose new incarnation debuted in Showcase #22 (1959). Green Lantern also graduated to his own series, followed by a new version of the old Justice Society of America team-up series, the Justice League of America, which bowed in Brave and the Bold #28 (1960). New versions of Hawkman and the Atom followed not long afterward.
"The Flash of Two Worlds"
Schwartz was aware that a few readers remembered the original Flash, Jay Garrick, who had not been seen since the cancellation of All Star Comics in early 1951. In fact, the original Flash made a brief appearance in the origin of the new character — as a comic book character whose adventures Barry Allen had read as a boy!
Making the original Flash a fictional character in Barry Allen's world was a clever idea and Schwartz and his writers could undoubtedly have left it at that. However, in 1961, they introduced a new twist: In Flash #123, "The Flash of Two Worlds," Barry Allen actually met his childhood hero, who was now said to reside on a parallel world occupying the same space as Barry's world, but vibrating at different frequencies so that the two never quite intersected. Since Barry's powers allowed him to alter his own "internal vibrations," this explanation opened the door for Barry to visit Jay more or less at will. In a distinctly meta-textual touch, the two heroes speculated that the comic book writers of Barry's world had written Jay Garrick's four-color adventures based on psychic impressions of Jay's real exploits on that parallel Earth.
This story evidently struck a chord with readers. The idea that one's favorite comic book characters were actually real people on some other world was an enticing one, as was getting two colorful super-speedsters for the price of one. "The Flash of Two Worlds" also appealed to the vocal minority of readers who had remembered the adventures of the original Flash. Those fans soon began clamoring for the return of other "Golden Age" heroes.
More team-ups between Barry Allen and Jay Garrick soon followed, leading to a 1963 guest appearance by Jay's old colleagues of the Justice Society of America (The Flash #137). Two months later, in Justice League of America #21, the heroes of the JSA met the Barry's Justice League in what would become an annual team-up. That story also offered names for the two worlds for the first time: The world of the JLA and the modern Flash and Green Lantern was rather chauvinistically dubbed Earth-One, while the world of Jay Garrick and the Justice Society was designated Earth-Two. (Usually, those numbers were spelled out, though there are many instances where the numerals were used.)
The parallel Earths concept was too good a gimmick to pass up and quickly popped up in various DC comics. Many of those stories were essentially one-offs, like World's Finest Comics #136, where Batman finds himself in an unnamed parallel world where he has no counterpart and Robin works with Superman, or the two-part story in Justice League of America #29-30 featuring the Crime Syndicate of America, evil Justice League counterparts from Earth-Three. A more tongue-in-cheek approach followed in 1968's The Flash #179, where Barry Allen finds himself on Earth-Prime, a world where he exists only in comic books; that story even allowed Barry to meet editor Julius Schwartz.
In the 1970s, the "multiverse" also became a convenient way to accommodate DC's latest acquisitions: characters originally published by Quality Comics (Uncle Sam, the Ray, the Human Bomb, et al) and Fawcett Comics (Captain Marvel and the Marvel Family). As those characters were added to the company "library," they were assigned to their own parallel worlds, dubbed Earth-X and Earth-S, respectively. The same was done in 1985 for characters from Charlton Comics (the defunct "Action Heroes" Blue Beetle, Captain Atom, the Question, et al) were assigned to Earth-Four.
While the total number of Earths was never quite infinite, the tally (including one-offs) eventually reached more than 20 — even more if we count "probable" worlds that were implied but never explicitly described. Still, few of these worlds received as much development as Earth-One (the default world for most of DC's "modern" stories) and Earth-Two. By the late sixties, most of the original JSA had returned and many were making frequent guest appearances in other books. One of those characters, the Spectre, even received his own short-lived title.
While Barry Allen and Jay Garrick had essentially the same powers, they were clearly different people, with different names, origins, and costumes, different appearances, and distinctive personalities. The same was true of most other members of the JSA and JLA; the two versions of the Atom, for instance, didn't even have similar powers. The coexistence of those characters presented no great conceptual problems or continuity issues.
The heroes who had been published continuously since the 1940s were another matter. Superman and Batman had been members of the JSA in the 1940s, albeit only in a few stories, and Wonder Woman had been a part of the team since 1942. All three of those heroes were also members of the JLA, which posed a question: Did they exist on Earth-One or Earth-Two?
The answer was: both. In fact, the Golden Age Wonder Woman appeared with her JSA comrades in Flash #137, but the "Big Three" were discretely absent the first four JLA/JSA team-ups, probably to avoid confusion with their nearly identical Earth-One counterparts. The Earth-Two Batman popped up briefly in 1966, in writer Gardner Fox's alternate ending to Detective Comics #347, Robin followed in 1967's Justice League of America #55, and the Golden Age Superman reemerged in 1969 (Justice League of America #73).
Other duplicates cropped up later, often by accident. Guest appearances in Earth-One stories of minor Golden Age heroes like Zatara and the Vigilante suggested that they, too, had counterparts on both Earth-One and Earth-Two. » SEE ALSO: Earth-1's heroes who were active during the Golden Age.
The Earth-Two Boom
While fans enjoyed reading about the differences between the heroes of Earths-One and -Two heroes, but the full potential in Earth-Two's characters was left largely untapped. Their moment arrived in 1976, when the Justice Society starred in the revival of the original All-Star Comics. The resurrected series fleshed out the Golden Age characters and their world, from the Earth-Two Robin's new role as a UN ambassador to Alan Scott's career struggles. Earth-Two's Superman now looked his age, as did Bruce Wayne, who was no longer Batman, but the police commissioner of Gotham City.
New Earth-Two characters were also introduced. The first was Power Girl, debuting in 1976's All-Star Comics #58, a more pugnacious (and pulchritudinous) counterpart of Earth-One's Supergirl. The next new addition, introduced in All-Star Comics #69 and DC Super-Stars #17 a year later, was the Huntress. Intended as an Earth-Two version of Batgirl, the Huntress was not merely an ally or imitator of Batman, but the aging Caped Crusader's 20-year-old daughter.
More Earth-Two characters gained their own strips. In 1977, wartime exploits of the Golden Age Wonder Woman briefly displaced the adventures of her Earth-One counterpart in Wonder Woman, a belated effort to capitalize on the live-action Wonder Woman TV series (whose first season was set during World War II). The Huntress earned her own feature in the final issues of Batman Family in 1978 and in 1979, the Earth-Two Superman got his own strip in Superman Family, set in the early fifties. Even the former Quality Comics heroes from Earth-X, the Freedom Fighters, got their own title, albeit set on Earth-One.
Exploring the Multiverse
This expansion of the DC multiverse suffered a setback with the cancellation or consolidation of various series in the infamous "DC Implosion" of 1978. In 1981, All-Star Squadron debuted, featuring the Golden Age heroes in their heyday of World War II; the series devoted much of its energy to resolving unanswered questions and apparent contradictions in Earth-Two continuity. A new "Whatever Happened to …" backup feature in DC Comics Presents filled in more blanks and Earth-Two characters were regularly teamed with Earth-One's Superman in the main story. The Huntress now had a backup series in Wonder Woman, while Earth-Two's Doctor Fate got his own feature in the back pages of The Flash. In 1984, children and protégés of the JSA (many of them newly invented for the purpose) received a new series called Infinity, Inc., essentially the Earth-Two analogue of the popular New Teen Titans series. In 1985, the modern JSA received a four-issue mini-series detailing their entire history in exhaustive detail, and of course the yearly JLA/JSA team-ups also continued apace.
As always, Earth-Two received the most attention of the theoretically "infinite" Earths, but the heroes of Earth-S were featured regularly, first in the Shazam! series, which ran from 1973 to 1978, then in World's Finest Comics and finally Adventure Comics through 1982. The original Captain Marvel and his friends also popped up in DC Comics Presents and Justice League of America.
Crisis on Infinite Earths
By the time of DC's 50th anniversary in 1985, the company concluded that the multiverse concept had run its course. While only three or four of the multiple Earths were really significant in any ongoing sense, the DC Universe felt far less cohesive than the Marvel Universe and some editors felt the multiple Earths were just too convoluted, particularly for newer readers.
Crisis on Infinite Earths was designed to take care of these myriad worlds and create a more friendly environment for readers. Some of this proliferation was the result of DC's acquisition of characters from other publishers (Charlton, Fawcett, and Quality). These publisher sets all inhabited their own parallel Earths.
The solution was a 12-issue mini-series which created a cosmic threat that destroyed nearly all of the parallel Earths and collapsed the remaining ones into a single, unified Earth. The history of the new universe was chronicled in a two-issue perfect-bound mini-series called History of the DC Universe, followed by high-profile "reboots" of Superman, Batman, and Wonder Woman. The doppelgängers were swept away, and with them, many of the trappings of the Silver Age that spawned the multiple Earths in the first place. The unified world was called "New Earth," and Cosmic Teams frequently refers to its continuity as "post-Crisis continuity."
Post-Crisis Crises (January 1986-2006)
Crisis on Infinite Earths "rebooted" the entire DCU, merging all Earths and characters into one streamlined world and timeline. But after this herculean effort, no one bothered to really helm the ship, in terms of continuity. Nobody could have guessed that after the game-changing Crisis on Infinite Earths would eventually lead to a full trilogy of crises for the DC Universe. Other cosmic crises followed, notably Zero Hour: Crisis in Time (1994), Infinite Crisis and 52 (2006–07), and Flashpoint in (2011).
In the years following the Crisis experiment, fans and writers inevitably began to pine for "lost" characters and other bits of continuity, so they find ways to reinsert them. One very unpopular Crisis change was that Superman, Wonder Woman, and Batman were no longer charter members of the Justice League. In the following years, a number of stories were written to try to shoehorn them back in, first as honorary or part-time members, and eventually as full members again. This kind of change is called the "retcon"—retroactively changing continuity, aka changing the past.
Another major omition was Supergirl, who was eliminated entirely because DC editorial felt that the Superman character should be the sole survivor of Krypton. It probably sounded great during a huddle, but fans were dying to see Supergirl again, and so she was reintroduced—but not as Superman's Kryptonian cousin. Instead a needlessly elaborate tale was concocted around the character and Supergirl became one of the most confusing characters in the DCU (remember: the goal was to make things more accessible for new readers). Naturally, Superman's "real" cousin, Kara Zor-El, was brought back in the end.
Zero Hour and Hyptertime
Continuity was sufficiently mismanaged so that it was necessary to invent another round of house cleaning called the Zero Hour. Not ten years after Crisis, this "soft reboot" (changing bits and pieces) was supposed to fix all the continuity chaos that had been created after Crisis. Some characters like the Legion of Super-Heroes were totally rebooted. This was because the book had become "too hard to follow." (I'd like to direct you to Marvel's X-Men, which infinitely more complex, yet has never had a hard reboot, and remains a top property.)
Less than ten years on, the concept of parallel Earths was too irresistible. For a time, any alternate timeline was explained as part of Hypertime. Similar to the multiverse, Hypertime was an infinite branching of the DCU timestream. "Tributary" timelines were said to diverge from the "main" timeline. And, sometimes those tributaries feed again back into the "main" timeline. Created by Mark Waid during the 1999 Kingdom event, Hypertime seemed an obvious attempt to explain rampant poor continuity. DC house ads began using the phrase "The Original Universe" when promoting an in-continuity book (set in the "main" timeline). Many others were referred to as "Elseworlds" (set in "tributary" timelines).
For example, following the Crisis, Power Girl was explicitly removed from any membership in the JSA. Here the timeline diverged and an Elseworlds tributary traveled on in which she was a JSA member; the main timeline continued without her as a member. Gradually, more and more stories were told placing her firmly back into JSA membership (cemented in JSA: Our Worlds at War). Why, this could only be because that erstwhile tributary was "feeding back" into the main timeline. Continuity is ever-changing.
Infinite Crisis and 52
It took a successful and skillful writer, Geoff Johns, to convince the company to bring back the parallel Earths in Infinite Crisis. Johns wove a clever tale about how certain characters (such as Superman of Earth-Two and Alexander Luthor of Earth-Three) had survived the destruction of the original Crisis and had been living in seclusion behind an impenetrable crystalline barrier. Luthor's henchman, Superboy Prime, was pummeling against the barrier and each blow reordered New Earth's history. Once free, Luthor birthed infinite Earths once again. Upon his defeat, they were merged back into a single Earth, but the leftover energy from his multiverse then expanded into a multiverse of 52 identical Earths. The 52 Earths were then corrupted by Mister Mind, who "ate" events from all 52 Earths, altering their histories and making each one unique. The mainstream DC universe was designated Earth-0.
This concept was fun but once again, DC failed to capitalize on it. With a veritable playground available for storytelling, it seemed that the parallel Earths were off limits to writers. This territory had been somewhat ceded to Grant Morrison, who conceived a series called Multiversity, which would further define the parallel Earths. But Multiversity was too slow to develop and instead, Morrison followed up with a third Crisis—Final Crisis.
Final Crisis was not invented as a full reboot, though. It did, however, reinvent the New Gods in a major way. It was also an attempt to introduce some exciting new concepts and characters, most of them conceived by Morrison. But without Morrison's own hand, those spin-offs floundered in mediocrity.
Flashpoint and the New 52
After all the effort put into Infinite Crisis, Final Crisis, and 52, it was surprising that in 2011 DC Comics chose to jettison its mainstream universe in favor of yet another total reboot. More than likely, the motivator was sales. Although DC's comic books sold fairly consistently, it faced increased, multi-channel competition from a variety of strong publishers. Marvel's movie franchise was going gangbusters, which could not have gone unnoticed by the higher-ups at DC's parent company, Time Warner. Editors at DC would need to think bigger.
Comic book series might now be considered "R&D" for film and television. In the span of a decade, DC's presence had exploded into successful video games, animation, and television series. One way to lure extra dollars from those fans was to offer an entry level comic book universe.
Flashpoint appeared to be another innocuous "comic book event," and many readers did not realize things were headed for a total reboot. At the end of the series, DC relaunched with 52 brand new monthly series that reinvented its characters and revived popular titles from the past. The post-Flashpoint universe was dubbed the "New 52." It also was a multiverse of 52 Earths. The New 52 multiverse contained an all-new Earth-2 and Earth-3, and it was fully mapped in 2014 in the long-awaited series by Grant Morrison: The Multiversity.
» SEE ALSO: A complete discussion of the origins of the Multiverse and its destruction in the Crisis on Infinite Earths is beyond he scope of this chronology. However, an excellent discussion of all the aspects of the Crisis can be found in Jonathan Woodward’s The Annotated Crisis.