Looks like an Italian "mannaia" (meat cleaver). The all steel construction is common for butchery cleavers in France, but here both the blade shape and handle shape indicates an Italian filiation.
As for the blade, it blends different features of a pennato (billhooks with a hatchet blade on the back) and a mannaia:
As far as I understood, on mannaie, the back edge was to crack the skull to get access to the brain, but it slowly evolved into something purely esthetical, with no real function. Probably as general steel quality increased, and there was no need to save the main edge. But on yours, the back edge has been clearly sharpened and used.
As for the handle, it's a rather interesting form I've never seen, but it's clearly one of the long time evolution of the handle shape we see on the billhooks from Pompei and Moregine:
We see other intermediary forms like this undated late Roman thing, halway machete, halfway billhook, halfway falchion:
And this later, 10-11th century Italian billhook:
It also evolved into a form of billhook with a socket handle, rather typical of Piedmont:
It's very interesting that on your mannaia, the evolution went to make both the back and front projection simply flat and square. I'm saving this into my personal data, cause it's another form of evolution of this handle termination. And it's really specific to Italy, or at most what used to be the Duchy of Savoy and the kingdom of Piedmont-Sardinia. So it's a bit hard to pin exactly where your mannaia comes from, but it surely is Italian, and I would likely say late 19th or early 20th century. If one day you want to part from it, think about me!
Edited to remove all exterior links. For some reason, even though using the IMG tags, the images won't appear in the post.