My first Black Powder experience was in 1969 when I bought a percussion Pedersoli Kentucky Pistol. I had wanted to buy an 1860 army .45 cal. revolver but they were sold out. It had a naval scene engraved on the cylinder and price was right around $100. The Kentucky Pistol I got was .45 cal. Couldn't figure out how to adjust the fixed sights, so just shot it to find how much I needed to compensate and then killed ground squirrels with it at my Grandpa's Ranch. Put it aside along with a jar of black powder (half full) and some Crisco patches and rarely used it after that.
When I moved to VT in 1998 I bought a "modern" muzzle loader for deer hunter and paid just over $100 for it. A few years later I got real interested in Rev War reenactments and bought a Traditions Pennsylvania longrifle. Took it down to a spot in Frog Hollow (honest to God name of the road) where I could shoot it and took along some Pyrodex that I'd used for my other unmentionable rifle. I just could not get that thing to fire at all. Then I remembered my half-filled jar of Black Powder from 1969, dug that out and tried it. Went off on the first try and was very reliable.
Then in about 2007, I think, I bought my Early Lancaster from tg who was a member here on the forum at the time. It's an absolutely beautiful rifle and I've been shooting it ever since.
So, in 1969 a Pedersoli Kentucky Pistol was my first muzzleloader.