Behind-the-scenes struggles and legal wrangling have played just as big of a part in the history of comic books as the colorful battles on the pages themselves. And one of the most complex and long-lasting disputes in the industry has focused on Captain Marvel—or at least the two distinct versions of the character that have coexisted in a state of confusion at both Marvel and DC for decades.

Like many comic book tangles, this dispute was made possible because of the debut of Superman. Soon after his first appearance in 1938's Action Comics #1, there was a deluge of knockoffs from publishers looking for a piece of the Man of Steel pie. Though most of these were fly-by-night analogues, Fawcett Comics’s attempt at its own superhero wasn’t an inferior model—it quickly became real competition.

ENTER: THE BIG RED CHEESE

Fawcett’s Captain Marvel was created in late 1939 by Bill Parker and C.C. Beck and debuted in Whiz Comics #2. On his first cover, Captain Marvel is shown carelessly throwing a car against a brick wall, as two criminals bolt out of the windows. In Action Comics #1, Superman made his debut by hoisting a similar car over his head and driving it into the Earth, as the criminals inside fled.

The similarities were unmistakable: Here were two caped strongmen with heroic squints and circus tights leaping around cities and battling mad (and bald) scientists. But while Clark Kent got his powers from his Kryptonian physiology, Captain Marvel was, in reality, a young boy named Billy Batson who would receive his powers by shouting the magic word “SHAZAM!” If Superman was the straitlaced Boy Scout, Captain Marvel earned his moniker of "The Big Red Cheese" through sheer camp, a wink, and a nod.

Seniority mattered little to young comic book readers, and once Captain Marvel found his footing, he was outselling Superman at the newsstand and beating him to the screen by receiving his own live-action film serial in 1941. But as Captain Marvel reached larger audiences, DC was in the midst of legal action against Fawcett for copyright infringement. The claim was simple: Captain Marvel was a bit too close to Superman for DC's comfort.

DC wanted Fawcett to cease production of the serial and comics by the early 1940s, but Fawcett fought to delay a court battle for years. It wasn’t until 1948 that the case actually went to trial, with the dust finally settling in DC's favor in 1954. Legally, Fawcett would never be allowed to print another Captain Marvel book. By now, though, the superhero market was near extinction, so for Fawcett, it wasn’t even worth it to appeal again. Instead, the publisher closed shop, leaving Superman to soar the skies of Metropolis without any square-jawed competition on the newsstands.

MARVEL CLAIMS ITS NAME

The next decade would see a superhero revitalization, beginning with DC’s revamped takes on The Flash and Green Lantern in the late 1950s, and exploding just a few years later when Timely Comics changed its name to Marvel Comics and launched a roster of heavy-hitters like The Fantastic Four, Spider-Man, and The Hulk, all by 1962.

Marvel was a buzzword again, and in 1966, a short-lived company called M.F. Enterprises tried to capitalize with a new character named Captain Marvel—generally considered one of the worst superheroes ever put to paper.

Marvel now needed to stop inferior comics from using its name on their covers, so it obtained the trademark for the Captain Marvel name and went about protecting it by introducing yet another character named Captain Marvel. This new alien version of the hero made his debut shortly after in 1967's Marvel Super-Heroes #12.

The character was born purely for legal reasons. According to comic book veteran Roy Thomas, Stan Lee only created a Captain Marvel at publisher Martin Goodman's insistence: "All I know is the basis of the character came from a resentment over the use of the ‘Captain Marvel’ name."

Comics are nothing if not needlessly confusing at times, and by the early 1970s, Superman wasn’t quite the sales force he used to be. In need of some fresh blood, DC turned to an unlikely source for help: Fawcett. The company had reemerged in the late 1960s as the publisher of Dennis the Menace comics, but its hands were tied when the superhero business revived since it was legally forbidden from producing new Captain Marvel books. So they did the next best thing by agreeing to license the character and his supporting cast to DC in 1973.

CAPTAINS IN DISPUTE

Now the world’s two biggest publishers both had high-profile characters named Captain Marvel. But there was a catch: Since Marvel owned the rights to the name, DC couldn’t call its new Captain Marvel comic Captain Marvel. Instead, all of his comics went by the title Shazam, as did the character’s live-action TV revival in the mid-1970s. Oddly enough, the name of the character himself was still—wait for it—Captain Marvel. So DC could retain the character’s name in the stories but couldn’t slap it onto book covers or TV shows. Only Marvel could monetize the name Captain Marvel.

Right after Captain Marvel’s first DC book launched in 1973, there was an immediate hiccup. The full title of the series was the slightly antagonistic Shazam: The Original Captain Marvel. That lasted all of 14 issues before a cease and desist order from Marvel turned the series into Shazam: The World’s Mightiest Mortal. Marvel, on the other hand, found itself in the position to keep its trademark by continuously pumping out more books with Captain Marvel on the cover, which is why the company’s history is littered with reboots and new versions of the character turning up every two years or so.

By the 1990s, DC had outright purchased its Captain Marvel from Fawcett, but it could barely promote him. There are only so many times you can put Shazam on a comic cover but refer to him as Captain Marvel on the inside without confusing your readers. So in 2012, DC and writer Geoff Johns decided to end the decades of confusion and simply rename the character Shazam, because, as John said, “everybody thinks he's called Shazam already.”

In 2019, these two characters that are seemingly forever linked will have another shared milestone when they both make their big screen debuts. Marvel’s Captain Marvel will hit theaters on March 8, 2019, with Brie Larson playing the Carol Danvers version of the character. And after nearly 80 years of switching publishers, changing names, and lengthy legal battles, Zachary Levi will play the title role in Shazam! a month later on April 5.