Wow that is neat! At 1st I thought the left figure was a mountain man in a coon skin cap HA! Guess we need to go gack to school and learn more geography-the way the world is going, they change country names faster than some people change underwear.
It is an ancient cylinder seal, see reference below. This one depicts a king, the large figure on the left, marching the conquered captives off to slavery. The large figure on the right is most likely the king's god, usually a hideous looking demonic type character. This piece may be a bit more rare than what you usually see for sale on Ebay. Take it to the nearest university that has an archaeological department, and ask them to identify the culture and era. I recommend that you keep it in your posession at all times, and not leave it there for them to research. A nice find, they usually sell on Ebay for $100.00 on up.
http://search.ebay.com/cylinder-seals_W0QQsojsZ1QQfromZR40
Historical note: Cylinder seals were first made in Mesopotamia, soon after 3500 BC. Paper had not been invented, so documents were written in cuneiform (wedge-shaped characters made into wet clay to provide pictorial symbols for words and syllables) on clay tablets and then wrapped in clay envelopes. The seals were used to make an impression (or 'seal') in the soft clay, to indicate that the message on the tablet was genuine. In the same way, important documents are still sometimes 'sealed' by making an impression in bright red sealing wax. People continued to use cylinder seals to 'seal' ancient documents for about three thousand years.
Reference: Mesopotamian Cylinder Seals by The British Museum