Just to muddy the waters further, let me introduce you to Marvelman...
When Fawcett stopped publishing Captain Marvel comics in the mid-'50s after the DC lawsuit, Len Miller, the guy republishing those comics in England, had Mick Anglo create a replacement, Marvelman. The differences between the characters, their supporting casts, and backstory was slight. He enjoyed some popularity in Britain; Marvelman even had international reprints. His various series continued until the early '60s.
In 1982, Marvelman was revived in the British anthology comic
Warrior, written by Alan Moore (later of
Watchmen and
V for Vendetta fame). Marvel comics, by then a behemoth of the industry, objected to his name. When the Moore Marvelman comics were licensed to American publisher Eclipse in 1985, they avoided Marvel's wrath by renaming the character Miracleman. Moore completed the story he'd started, then turned MM over to Neil Gaiman. Gaiman's storyline was cut off when Eclipse went bankrupt.
Todd McFarland bought many of the assets of Eclipse, intending to publish a new Miracleman series. But the rights to this character were murky, with claims from Anglo and Gaiman keeping Miracleman from appearing for years. Finally, Marvel stepped in with buckets of money and cleared up the rights issues for good (allegedly). They've since republished all of Moore's run and Gaiman's run up to its abrupt cut-off. Gaiman was trumpeted as planning to finally complete his projected story, but solicitations were later canceled and nothing has been heard about it for a couple of years, except for occasional rumors.
Marvelman / Miracleman was a fascinating deconstruction of superheroes by Moore (without completely invalidating any of the previously-published adventures, no small feat). He had most of the trappings of Fawcett's Captain Marvel, including sidekicks called Young Marvelman and Kid Marvelman, who gained superpowers when they spoke their hero's name.
Maybe think of him as a pseudo-Captain Marvel. But, guaranteed, he's definitely not your dad's Captain Marvel...