Captain Marvel ruled the 40s

One of my favorite covers from the Golden Age

Captain Marvel (now referred to as SHAZAM) was the biggest superhero in the world during the height of comic book sales.  His various titles carried circulation numbers in the 6 Million range, compare that to the biggest selling comics today which would be considered blockbusters if they sell 180,000 copies.

The Good Captain was the first Live Action Superhero to be put to film too, in THE ADVENTURES OF CAPTAIN MARVEL serial from 1941.  It's considered a classic among serial fans and in my opinion it holds up to this day.  It was a very serious version of Captain Marvel which surprises many of his fans today because the character became more known for his tongue in cheek adventures including the addition of 'family' characters like Mr. Tawny the talking Tiger and Uncle Marvel who was a roly poly old guy who stumbled his way through adventures in a union suit.

The original Captain was deadly serious-- and in a take that is the polar opposite of Batman from the same era, he actually got better when they stopped taking themselves too seriously.

The good Captain is possibly the most maligned of the great characters.  The focus of a lawsuit filed by DC Comics who claimed Cap was a ripoff of Superman (he wasn't), the lawsuit raged on for nearly a decade before Cap's publisher Fawcett Comics decided that superheroes were falling out of favor in comic books and opted to cancel all the Marvel titles.

DC eventually bought the Fawcett characters but by this time Marvel Comics (known as Timely Comics in the 40s) wisely opted to trademark the name Captain Marvel when the option came up leading to the original Captain Marvel being forced to rename his title SHAZAM when it was eventually relaunched in 1973.

Magic didn't strike twice, however, and fans objected to the jokey nature of the strip.  Since that time Captain Marvel has been relaunched several times with mixed successes but none have been able to capture the spirit of the 40s series.