1990s, and an accident waiting to happen. Granddad, in the 1990s bought up tons of these, and gave them away as gifts. About 10 years later, he gave me one as my first knife. While doing some whittling, the flimsy bushing holding the pivot pin in just fell off, and the knife pretty much exploded. I still have one intact, as well as a much smaller model that was my great-Granddad's, and I keep those for the sentimental value. There are many in my collection, that quite frankly, are what I'd normally view as cheap junk, but have high sentimental value because of who they belonged to.
Believe it or not, I was pretty much the one that got my family into actual Swiss Army knives. My other great-grandfather (on my Grandmother's side) owned a Pioneer, just didn't use it much. Around the time I got into Scouts, I bought a Fieldmaster model, and then just kept buying them, and am becoming a rather serious collector more than just a user.