Mexican?
 

Artzi describes this as: “a long machete sword, most probably from Mexico or otherwise a neighboring country in central America. Nicely re-curving blade, double edged, 23 inches long. Long black horn handle carved as a human figure and set with colored stones inserts. Tooled leather scabbard. Total length 32 inches. very good condition. Minor edge nicks.”

The handle looks African to me.

Artzi adds in an e-mail: “Very good question on the origin. I am not sure at all and to add to my confusion this sword was purchased together with other African lots. But the blade shape and the scabbard are much Mexican.”

THESE COME FROM GUATEMALA IN CENTRAL AMERICA. THE HORN HANDLE AND FIGURE ARE TRADITIONAL FOR THESE, MOST YOU SEE ARE SMALL DAGGERS. THERE MAY BE A POST ON THEM IN THE FORUM TRY A SEARCH FOR GUATEMALA.YOURS IS A NICE EXAMPLE.

Nicely caught Vandoo!!!!
The scabbard looked Mexican to me, but that carved hilt really does look African. Is there some significance to the figure, and does it occur on other items from these regions?

Bingo!
 

Good call! Apparently the usual small knives come from "Chichicastenango, also known as Santo Tomás Chichicastenango, is known for its traditional Maya Indian culture.
The Spanish conquistadors gave the town its name from the Nahuatl name used by their soldiers from Tlaxcala: Tzitzicaztenanco, or City of Nettles.
Its original name was Chaviar."

Just reread the OP, and that Artzi was already spot on with the classification but with the African possibility, so my response overlooked what he had already said. His classifications are always in my opinion extremely reliable so please pardon my oversight.

just for reference
 

Virtually all the other examples I have seen have been relatively small knives from from Chichicastenango. Clearly these are for the tourist trade. I picked this one up from e-bay just for reference.

I think the vendors is a bit optimistic:
"Vintage Chichicastenango Knife Guatemalan Handmade Old Ceremonial Mayan Fighting knife."

The one from Artzi still stands out because of its size. It is also nice that it lacks the crude engraving for the tourists.

Is there really anything Mayan about the style of the figure? Yes, most Mayan figurines have headdresses, but I haven't seen anything like this.

Marcus, thank you again for posting this as well as following through with these additional observations. It means a lot to have these kinds of informational entries to add to archived data which benefits us in future research. Much appreciated!