John Stewart first appeared in the pages of Green Lantern in December 1971 when Neal Adams came up with the idea for a substitute Green Lantern. During a conversation between Adams and editor Julius Schwartz, Adams offered that given the racial makeup of the world he should be black because it makes sense. He became DC’s first black superhero.
For many of us who didn’t read the comics, he was the only Green Lantern we knew of. This is because he was the Green Lantern for the Justice League and Justice League Unlimited series.
He has been a major recurring character in the Green Lantern mythos and has been the lead in various series starting with Green Lantern volume 2 185-200. Starting in issue 201 the book became Green Lantern Corps until 224 when it was cancelled. For a time he led his own book titled Green Lantern: Mosaic where he was the administrator of Mosaic World. He gained Guardianhood through his actions here.
I have always liked Stewart because of his background. He was originally an architect, but was retconned to be a US marine from Detroit. I don’t mind the change because neither had him starting off as a criminal or having a misunderstanding that lead to him being arrested for a crime he didn’t commit. He is just a positive black superhero who has more than once been the lead in his own books.