Justice Society Of America - Explained
4. The Original Justice League - The JSA's Beginnings
As previously mentioned, the Justice Society of America was first introduced in All Star Comics #3 in 1940. It was the first established team of superheroes in the comics medium, and the one that would set a precedent for all subsequent super-teams thereafter.
Co-created by Gardner Fox, Everett E. Hibbard and Sheldon Mayer, the JSA comprised characters from not just DC, but also All-American Publications. The original idea was that everyone serving on the team could only do so if they didn't have their own self-titled comic. If they did, they'd be referred to as 'honorary' members, a title that was even given to Batman and Superman, who were considered founders despite never appearing in the original run of comics. (It would take several decades until the story of how they co-founded the team would be revealed, in 1977's DC Special #29.)
This is where things start to get confusing, however. While there's not much to explain about the original JSA other than they walked, talked, looked and acted like the Justice League readers are more familiar with, the team would soon find themselves in the grip of frequent retcons that took them out of the spotlight.
The Silver Age was in, and the Golden Age, as they say, was very much out.