[quote=thewizardguy]
Yhe barbarians themselves seem rather generic at this point in time, as they haven't made a large appearance in the story as of yet, but the tattoo aspect reminds me of African tribes. The heavy clubs makes me think of Orcs more than anything, but it seems strange that such a barbaric people with a seemingly low level of technology would have controlover a large swath of land, suggesting they don't have any adversaries of suitable size to challenge them. Quite probably, the Empire just doesn't have the men to push forward.
[/quote]

I was actually veering more towards ancient Rome, in the way that by the end of its time, many of its armies were comprised by peoples from all over Europe - and Africa - because the Italian home states couldn't provide the troops alone. 

You're right though, the Empire just hasn't gone that far. It could be for several reasons, and I'll just let it play out along the whims of the players, but here's a few ideas:

- the north holds no strategic importance

- the north holds no resources worth conquering

- the Empire is busy elsewhere, and has never had time or resources to press forwards.

- the Empire tried to press forwards, perhaps some years prior, and has been unable to recoup its losses since the failed campaign.

- no one believed that warring tribes of roaming savages would unite to threaten the Empire directly

Endless really, but it's just something to keep the ball rolling.

EDIT: I agree, we have excellent character diversity so far.