I did this year's ago on twitter, and was pleasantly surprised and horrified by the results, but,
Just a wee thought.
depressing but I think the earliest I can remember is like, the walking dead
What's more depressing is you might have been too young for the launch of GTA San Andreas, oohgh
Oh yeah, I was old enough probably, but I wasn't into those games at the time
These are quite early, but, regrettably, I dunno how good they are? They tie in to a movie that, admittedly, is not white, but it's a product for that movie.
it says a lot that the only easy mode early answer is "sports games" and i think "protagonist" is a stretch
I wouldn't rate it, honestly. They're built from real world rosters, and those can get very large. I also don't count some ensemble games as hard, Streets of Rage 1 being very early, but, 1/3 of your playable characters. That's not a black story, honestly.
There are older games, but maybe the first one in my personal play history is Final Fantasy 7? Assuming JRPG party members count.
The first time I remember it feeling like an intentional, considered decision was maybe Beyond Good & Evil?
Implicit, but worth a mention, the Kongs in Rare's Donkey Kong Country/Land games are very 80s/90s Cartoon Black-Coded (the kids and their rap music and boomboxes and backwards hats, plus whatever the hell was going on with Funky Kong), which should raise some dang eyebrows because they're... literally cartoon apes???
yes, but then you're going to get people claiming they're actually white, or white passing or etc etc etc, so maybe best to just ignore that category.
also ff4 has Yang as a playable/protag character, but that feels like more of squaresoft playing in genre space than intentional representation.
first thought: GTA San Andreas
second thought: probably the Tony Hawk's Pro Skater series
"Recall" is GTA San Andreas.
"That you can think of/find without googling "first black game character" is a much harder question. My answer is Streets of Rage 1. 1991.
old dungeon crawler for the NES, or SNES. to hell with remembering the name of it, but the little town outside the cave had plenty of diff people
Those are characters, and black characters, like, at ALL on the NES is something I really don't recall at all, but, those aren't protagonists.
NGL I'm so out of it I absolutely did indeed miss the 'protag' part of the post, true.
I would go with Prince of Persia, though AFAIK they never specifically call it out outside of context clues from the story and setting.
Prince of Persia was my first thought as well. It's the nature of representation -- sometimes your identity is explored in detail, sometimes you're just an anonymous Persian prince.
Without having read the comments, the earliest that comes to mind is Shadowman (1999). The overall aesthetic feels very much like a video game based on a comic book written by two white dudes in the 90s. 
I really enjoyed Shadow Man at the time but, yeah, it was definitely written by white people
🤔 My first guess would be "Bruce Lee" from 1984. 
"The Castles of Dr. Creep", also 1984, has a black character as one of the playable options, but the manual doesn't have a backstory, only describing the 2-player protagonists as "you and your companion". 
Another entry from 1984, "The A Team" has you play as B. A. Baracus (a role made famous by Mr. T) on the Atari 2600, in a re-skin of an older game named "Saboteur". 
Imagic's "Riddle of the Sphynx" (1982) casts the player as the "Prince of Egypt", but it doesn't specify which era or dynasty.
🤔 Depending on how one defines "video game" and, ahem. ancient Sumeria, "The Sumerian Game" from 1964 (!) is a text-based resource-management game that casts the player as leaders in the Fertile Crescent around 3500 BC. This game would later be ported as "Hammurabi" or "Hamurabi" [sic] to the BASIC language in 1971, and there would be numerous imitators after that.
