Eastern Sword: Origin and Age?

[Tatyana Dianova]

Thank you guys for your replies! This small sword appeared even more interesting, than I have thought. I like the pirate version the most , at least it can explain why the sword have seen so much use during its life.
It is really an eBay find, where it was sold as a Kastane type sword. I bought it, because I liked its fittings.
I want to add one more picture: the monster head on the guard. Enjoy!