An Odd Knife

An Odd Knife:

Every once in a while you come across a knife that defies identification. This knife came out the Northwest corner of the US, but it may have originated elsewhere. Based on the Patina I would date it early 20th century or later 19th century. Usually the blade's shape clearly defines the function of the knife itself. The handle is often less influential. This knife poses a real conundrum, its shape and function are both puzzling. It appears to be designed to slice something on a countertop or cutting board, the very utilitarian handle being offset to allow the users knuckles to clear the work surface. The handles appear to be plain Birch scales held by steel pins.

The sharp upward sweep of the blade would suit a rocking, cutting motion, but of what? The heavy weight blade (1/4" thick) is professionally forged and completely unmarked. The back of the blade does not have any signs of being hammered or beaten on. Someone scoured up the blade surface with a power grinder. I have removed as much of the damage as possible with wet-dry paper, bringing the edge back in the process.
I have asked all of my knife friends and no one seems to know what this knife was designed for. I even sent a photo to Bernard Levine, a renowned knife expert. He could offer no explanation either. Should you have a suggestion please email me at ghdave2@hotmail.com.