Swords in Art -- what is this?

[arsendaday]

I am only speculating that the reverse curve in this case is simply the result of a technical painting error that the painter didn't consider important enough to correct without visible trace.

If it wasn't for the scabbard I would totally think that the guy has a double edged European sword and the painter just screwed up. The scabbard though tells me that this is some kind of curved (recurved) sword. But even if the painter made a mistake in drawing the sword blade, the person is still holding the sword wrong. As you rightfully observed judging by the hand position the edge could be on the other side, if it is not double sided sword of course. The only weapon that I know of that has a recurved blade and a sharp edge on the concave side is the Turkish yataghan. Of course in this case the handle is completely off.