For many years, Bob Kane was credited as the creator of Batman. True, Kane did conceive of a comic book hero named "Batman" and drew many of his early adventures. However, for much of the Dark Knight's publication history, his co-creator, Bill Finger, went uncredited.
This was especially galling since students of comic history would come to realize that Finger, not Kane did the lion's share of work in creating Batman. Kane negotiated himself a sweet contract, including sole credit, while Finger died in poverty. The story to get Finger a co-creator credit is documented in Batman & Bill. For more info on Finger's biggest contributions to the Batman character and mythos, read on.
10 He Redesigned Bob Kane's Batman Costume Into The Now-Iconic Look
While Finger was a writer, not an artist, it's him who designed Batman's original costume. Kane's initial concept for Batman is unrecognizable. The character is more clearly modeled on Superman and other pulp heroes, with a plain red costume, a simple domino mask, bare hands, and blonde hair. The only bat symbolism in the design is pair of wings on the hero's back. Finger suggested the black-and-grey color scheme, gloves, the bat symbol, replacing the wings, and swapping the domino mask for a cowl. This is, of course, Batman's iconic design, one that much better stands on its own and with a much more prominent bat motif. The only carryover from Kane's concept art was the yellow utility belt.
9 He Came Up With Batman's Secret Identity Of Bruce Wayne
As the writer of the pair, it was Finger who fleshed out Batman's character beyond Kane's initial premise. One of the most important details about Batman, his true identity of Bruce Wayne, was Finger's invention. The name didn't spring entirely from Finger's imagination, but rather from two sources. Batman's first name was inspired by Robert The Bruce, the 14th century Scottish King. "Wayne" came from Revolutionary War soldier "Mad" Anthony Wayne. Finger's reason for looking back to the early days of America was that "Wayne, being a playboy, was a man of gentry. I searched for a name that would suggest colonialism."
8 He Also Came Up With The Name Gotham City
More than just about any other superhero, Batman's home of Gotham City is an integral part of him and a character unto itself. Bruce is his city's savior not just through his individual acts as Batman, but how he inspires his fellow citizens to act in his image. It may have started as just a caricature of New York City - "Gotham" being an old journalistic nickname for the Big Apple - but across Batman's long history, Gotham has evolved across numerous different lines. It's a place that can be anything - an exaggerated art deco metropolis out of a film noir, an overcast crime-ridden den, a maze drenched in neon, and plenty more. According to Jim Steranko, a legendary comic artist with a side gig as a comics historian, the moniker "Gotham City" was Bill Finger's invention.
7 He Wrote Batman's Origin Story
Everyone knows Batman's origin story. Eight-year-old Bruce Wayne, the scion of wealth and power, sees his parents murdered in front of him by a mugger outside a movie theater. He then makes a promise to his parents, and himself, to rid his home of their evil that took their lives. After years preparing for his crusade, he is unsure what name to adopt to complete it. When a bat crashes through his window, he realizes the visage he must adopt to strike fear into the hearts of the wicked. This tale was first told in Detective Comics #33, a comic written by Bill Finger.
6 He Designed The Batmobile
To traverse Gotham City and beyond, Batman has several vehicles in his arsenal, but the most important is the Batmobile. Over the years, the Batmobile's design has varied, ranging from a simple sports car with a bat motif to an outright tank; most depictions fall somewhere in between.
The Batmobile debuted alongside its owner in Detective Comics #27, written by Finger with art by Bob Kane. It was initially depicted as a simple red sports car, a fitting vehicle for a man of Bruce Wayne's wealth and stature. Finger, however, eventually redesigned it to have a bat motif and coined the "Batmobile" moniker.
5 He Introduced The Batcave Into The Comics
Just as Superman has his Fortress Of Solitude, Batman has the Batcave. Batman's subterranean headquarters, built beneath Wayne Manor, is where he goes between nightly patrols and where he conducts the lion's share of his detective work. Its design has varied over the years, as has its personal significance; some stories depict it as the cave where Bruce fell in as a child and acquired his fear of bats. The cave first appeared in the 1943 Batman film serial, but Finger brought it into the comics in Detective Comics #83 a year later.
4 Bill Finger Created Robin
Superhero comics, especially in the early decades of their existence, are meant for kids. That's why sidekicks exist; if the hero was who the reader wanted to be, the sidekick was a closer reflection of who they were, and thus who they could more closely project themselves onto. The most famous superhero sidekick is Robin, the younger half of the Dynamic Duo. The first Robin, Dick Grayson, was a co-creation of Finger, Kane, and Jerry Robinson; he first appeared in Detective Comics #38. Drawing on another famous fictional detective, Finger intended Robin as the Watson to Batman's Sherlock Holmes, i.e. the character the detective could explain their deductions to.
3 Giant Props Were His Trademark
One of the trademarks of Bill Finger's Batman stories is the inclusion of giant versions of everyday items as props. Gotham City, as written by Finger, was filled with giant type-writers and sewing machines. While the prevalence of these items faded after the Silver Age once Batman gravitated towards realism, they were some lasting influences, such as the giant penny in the Batcave. In the segment of New Batman Adventures episode "Legends Of The Dark Knight" homaging Silver Age Batman, and especially stories written by Finger and illustrated by Dick Sprang, the Joker robs a music museum and traps Batman & Robin in an unconventional death-trap; the strings of a giant piano.
2 He Wrote Batman #1
After the success of Batman's adventures published in Detective Comics, he and Robin got their own starring series in 1940, titled simply Batman - Finger wrote issue #1. Aside from being a landmark moment in the character's publication history, Batman #1 introduced the Joker and Catwoman as two of Batman's most important adversaries. Specific details differ based on different accounts, but it was Finger & Jerry Robinson who turned the Joker's design into a replication of Conrad Veidt's The Man Who Laughs.
1 He Co-Created Several Of The Iconic Villains And Supporting Characters
Batman's rogues gallery is a big reason why he's a premier superhero; a hero is only as good as his villains, after all. As the writer of many early Batman tales, Finger created several more enduring villains than just the Joker and Catwoman. Alongside Bob Kane, Finger created the Penguin (introduced in Detective Comics #58) and the Scarecrow (World's Finest Comics #3). Finger and Dick Sprang later introduced The Riddler in Detective Comics #140, while he and Sheldon Moldoff co-created Clayface and Calendar Man, in addition to supporting characters like Betty Kane/Batgirl I, Bat-Mite, and Ace The Bat-Hound.