Re: 50's comic-book heroes
New or at least majorly revamped superheroes in the decade of the '50s:
Captain Comet (1952)
Krypto The Superdog (what, he doesn't count?) (1953)
The Batmen of Other Countries (a goofy story, but strangely important to DC continuity) (1955)
Martian Manhunter (1955)
Flash II (Barry Allen) (1956)
Batwoman (1956)
The original Legion Of Superheroes (Lightning Lad, Saturn Girl, Cosmic Boy) (1958)
Challengers Of The Unknown (sort of supers, anyway) (1957)
Congo Bill & Congorilla (1957 &1959- originally just an adventure strip, but got superpowers within the decade)
Supergirl (1959)
Green Lantern II (Hal Jordan) (just squeaks in at the end of '59)
Aqualad just missed, in 1960.
Jimmy Olsen first became Elasti-Lad in 1958, too.
The late '50s at DC saw a lot of sci-fi action heroes who wound up as part of their eventual superhero universe as well:
Space Ranger (1958)
Adam Strange (1958)
Tommy Tomorrow (1958)
Rip Hunter (1959)
Plus there were several other action heroes from different time periods who blurred the line into superheroism, like Tomahawk, Nighthawk (a masked cowboy) and a few others.
Timely's brief comeback in the early '50s only recreated '40s characters, except for Venus (who wasn't much of a superhero) and a few monster characters who've been retconned into supers. As a bit of trivia, Patsy Walker (who later became the heroine Hellcat) first appeared in the Atlas romance comic Patsy & Hedy in 1952. There weren't any significan indy heroes created in the '50s- only the most popular of the non-DC heroes still had series at the beginning of the decade (the Marvels, Doll Man, Plastic Man), and all of them had died off by 1954 or so.
"Who know what evil lurk in hearts of men? Not me, maybe that guy over there!" - Win Eckert as Bizarro-Shadow
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