Looks like some kind of butcher knife,but who knows?Judging by the pitting on the blade i would say that it is no early than the late 19th century.Thats just my opinion from the pic.Nice neat old knife
Looks like it was crudely made from an old saw blade. Thin steel, just thin edges, home made wood handle. Sometimes these knives turn out to be knives made by soldiers during WW2, or just made by farmers for farm use. The thin blade would not have made a good fighting knife.