First appearance: Smash Comics #1 (August 1939)
In his next appearance, he's able to turn invisble.
From Who's Who: The Definitive Directory of the DC Universe Vol. XIX (September 1986):
from Who's Who: The Definitive Directory of the DC Universe Vol. XI (January 1986)
From Who's Who: The Definitive Directory of the DC Universe Vol. XII (February 1986):
Many years after his introduction, DC made him the brother of Captain Marvel Jr. (originally a character from Fawcett Comics).
First appeared in Crack Comics #1 (May 1940):
From Who's Who: The Definitive Directory of the DC Universe Vol. XVIII (August 1986):
from Who's Who: The Definitive Directory of the DC Universe Vol. XIX (September 1986):
First appearance: Crack Comics #1 (May 1940)
Technically, the group "Freedom Fighters" was a creation of DC comics; but all the characters that were originally members had previously been published by Quality Comics.
They were formally introduced into the DC Universe in 1973 in issues #107-108 of Justice League of America:
though Golden Age stories of many of the individual Quality characters had been included in things like the 100 Page Super-Spectaculars prior to then.
First appearance: Smash Comics #13 (August 1940)
First appearance: National Comics #1 (July 1940)