I have seen pictures of rocker locked folders dating back to the 1800's.
I submit that not all locking knives are non-traditional.
Sure there are. Locking folders go back a very long way. When John Wilkes Booth was killed at Garrett's barn, he had a folding pocket dagger on him. Looked sort of like the Case swing guard folder from the 60's. Old design. And in Spain, the Navaja goes back a couple hundred years. But a very large amount of the locking folders from a bygone era were made as weapons. They never were that popular for the common working man, or they wouldn't be so rare. Growing up when I did, I almost never saw a locking blade knife in the hands of any of the men I was around. In fact, the only locking blade knives I saw in the 1950's were the Italian switchblades that dad and Uncle Paul and most of the men I admired, called a punk's weapon. They were openly disdainful of them. I guess I inherited a lot of that attitude growing up, as I never was tempted to have a knife that the blade locked. Our scout master, Mr. Van told us that he'd better not catch any of us with one. It seemed to be a sociological thing perhaps of the era.
Going back 50, or even a hundred years, locking blade knives seem to be a rare thing to find examples of. Most of the well used knives we find from the early 20th and even the 19th century seems to be slip joints of some type. Cattle, Barlow, jacks in many forms. There just is not that many example of well used lockblades from long ago.
Carl.
