Are you talking non-retconned or the actual first in the history of the comics? I'm more of a Marvel guy than a DC on, so I think on Marvel's side, you'd have to consider Gabriel Jones as it's first black "hero", then Bill Foster (Goliath), but he didn't become Goliath until issue #24 of Power Man, in between Gabriel Jones and Goliath's first appearance, you didn't have a black superhero at Marvel (excluding The Panther) until the Falcon in 1969. So, I guess it would go...
1. Bill Foster
2. Black Panther (excluded)
3. Falcon
4. Luke Cage
5. Brother Voodoo
6. Blade