Not sure about what was the earliest game I played, but it was on a 386 in the early 90's. Maybe one of these:
DuckTales: Quest for Gold:
Scorched Earth: (image wasn't appearing so I quickly upload one)
I loved DuckTales... It's where I got my start in trading stocks haha.
Scorched Earth may have been the earliest though. By DuckTales, I had played a few PC games. Didn't have a PC myself yet but so it was always rarely upon visiting somewhere. Earliest ones were Battle Chess, Prince of Persia, Space Quest... 2 or something, a pretty early one (I know it when I google it), Terminator (the Bethesda precursor to Elder Scrolls).
That last one was probably my earliest
serious PC gaming memory. The others were briefly played during holidays when I'd visit for Christmas or such. Terminator though, I played for a week when I stayed with my cousin, and for me it's basically where my future love for GTA and open world began haha.
I always topics like this as opportunities to mention the otherwise basically-never mentioned The Terminator. I guess it's basically where Bethesda got their first-person open world start before Elder Scrolls (1994) and Daggerfall (1996). You think about GTA, early open city games with shootouts, attacks, stores, etc like Shadowrun (Genesis). Terminator basically had open world sort of walk around, steal or shoot shit, really darn early on -- and it's a huge open world.
"The game takes place within a huge (roughly 10 miles by 6 miles) 3-D rendered area of central Los Angeles. The game area runs roughly from Beverly Drive to Central Ave (lengthwise), and from Mulholland Drive to National Blvd (vertically). A game map is included in the box for reference. Though the buildings and their placement within the world is generic, and highways/overpasses have been removed, the streets and their layout are largely accurate. The game also includes some landmarks, such as Dodger Stadium, Griffith Park, and the Silver Lake Reservoir."
https://www.youtube.com/watch?v=6Ix9iD64pV4
That aside, I do have a few brief earlier memories. If I had to guess, I'd say it was either Scorched Earth or probably Battle Chess.