In any event, some time in 1961, Marvel publisher Martin Goodman saw that superheroes were beginning to do well for DC Comics. How Goodman came to this realization is something we will probably never know for sure (there are a lot of stories, but none of them, to my knowledge, have ever really been proven – if they were, feel free to let me know! The most prominent one has always been that Goodman was golfing with SOMEone at DC…even the who changes from story to story…and they were bragging about how good their Justice League of America title was selling), but the fact remains that in 1961, Marvel was set to debut their own superhero comic, the Fantastic Four.
However, they did not want everyone to KNOW they were publishing a superhero comic yet.
If you look at the first two issues of Fantastic Four, they do not appear much different from the current Marvel monster books, which were Marvel’s highest selling titles at the time (Tales to Astonish, Journey Into Mystery and Tales of Suspense).
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There are two possibilities for why Marvel would do this. The first is that they were hesitant to upset DC by competing with DC’s burgeoning superhero line of comics, for fear it would affect their distribution deal, but when the first two issues went by without problems, they figured they’d just let the cat out of the bag.
The second is that Marvel just plain ol’ wasn’t sure that superheroes would sell, so they decided to hedge their bets by keeping a monster presence on the covers.
In either event, after Kirby finished his monster-centric cover for #3, Marvel decided that they did not have to hide the superhero aspect of the Fantastic Four any longer, giving us the cover to #3…
And the rest, as they say, is history.