In 1939, Roscoe K. Fawcett, a second-generation executive of the Fawcett Publishing Company, looked at the success of adventure comic books and decided it was time to get into the superhero business.
In a 1997 interview by P. C. Hamerlinck, reprinted in The Fawcett Companion, Fawcett recalled:
The surveys showed the greatest comic book readership was among 10 to 12 year old boys. I said, “Give me a Superman, only have his other identity be a 10- to 12-year-old boy rather than a grown man.”Historians are rightfully dubious about such recollections being complete and accurate since we all try to make sense of the past in our memories, sometimes in ways that serve our desires. Were there indeed market surveys at the time? Was Fawcett accurate in describing exactly how this new hero would appeal to boys?
One element of this quotation leads me to trust the general outlines of Fawcett's story: he acknowledged that he was trying to replicate the success of Superman, like everyone else in comics--though for legal reasons most couldn't acknowledge that fact.
Before the end of 1939, the Fawcett company created some "ashcan" issues of a new comic book, printed without color and hand-bound, to secure its copyrights and to show to potential advertisers. This proto-magazine was titled Flash Comics or Thrill Comics, depending on the copy. The lead hero was named Captain Thunder.
Captain Thunder wore a cape and tight coveralls, not unlike Superman. What set him apart was his alternate identity. Rather than being a mild-mannered reporter, idle playboy, or police detective, in his non-heroic life the superhero was a boy about twelve years old. His tale thus directly addressed the daydreams of the bulk of comic-book readers.
By the time Fawcett published the second issue of its magazine, competing trademarks had forced the company to change several names. The comic book was now called Whiz, though nonetheless labeled issue #2. And Captain Thunder had become Captain Marvel.
Captain Marvel was a quick and lasting success, outselling all other superheroes in the mid-1940s and inspiring several spin-offs. The magazines was still doing relatively well over a decade later, when Fawcett decided to walk away from the declining comic-book business to settle a long lawsuit from DC over--what else?--having plagiarized Superman.
Back in late 1939, the executives at DC Comics probably saw the same market data that pushed Roscoe Fawcett into asking for a comic-book hero who was also a kid. Some folks at DC might even have gotten a peek at the "ashcan" story of Captain Thunder. In any event, that was the market environment in which Robin made his debut in the April 1940 issue of Detective Comics.