Maybe not exactly the requirements for the answer your looking for, but I'd say Carthage. Mainly because I really know nothing of Carthage except... you know... Hannibal... and the Punic Wars.... I never figured out what culture they were, whose ancestors they are. I've heard different things like Hebrews and such. Were they a culture uniquely their own, now it's just gone? The stuff about their government being similar to the Roman republic is interesting. Such a powerful nation back in the day, can it be that they're completely gone, with nothing to show for it but some parts of history?

And the Carthage faction in EB looks stupendous, woo!