[img]http://upload.wikimedia.org/wikipedia/commons/c/cf/Yuan_chinese_gun.jpg[/img]
Ancient Chinese hand cannon from the 1300s.
The 1300's aren't exactly considered "ancient"

But I think a European hand cannon would make more sense, as it was wooden, and doubled as a spiked club once you fired the single pellet.
Funny, Skyrim basically has robots (which remind me a lot of those in Thief Metal Age, btw) , but a firearm?! OH NO!