lol Black Panther was created by Jack Kirby and Stan Lee, two white guys. Knowing Stan Lee probably just Kirby created him and Lee stole credit.
No he wasn't the first black superhero.
You would have a better case of arguing Lothar, the sidekick for Mandrake the Magician was the first black super hero. Both african inspired though, not black as in black american.
Priest made the whole Wakandan lore that most of you love today but he didn't make Wakanda, Kirby and Lee from the beginning made him from a fictional african country Wakanda. So you are just wrong.
You literally just made shyt up out of ignorance, something a lot of you do, which is strange as you are on the internet and can easily search shyt out.
You want a black american hero, you have your cowboy myths, John Henry, Luke Cage, Mister Terrific, Black Lightening, John Stewart, Steel, Static, Blood Syndicate, Icon, Rocket, Spawn, Black Vulcan, Falcon, Blue Marvel, Cloak, and some others.