I hate to even go here, but the handle looks in way better condition than the blade, to me thats a bit of a red flag...in fact the handle looks like it was actually darkened quite a bit, perhaps with leather dye etc???
and that type of handle (sans carved decoratations) is usually associated with late 19th/ early 20th century English cutlery...and may have once had a silver ferrule and a standard commercial type blade...the blade hafted there is nothing like any carving knife Ive seen, perhaps implying a re-haft, but why rehaft such a wasted blade?? ...all in all, another red flag...
Sorry to be a doubting Thomas, especially since Im no expertand cant examine the piece in hand etc...but based on what I see, I have my doubts
about it being really old etc...