[Barbarian]

I enjoy exercises like these, but there are a lot of unanswered questions that come along with your scenario.

Examples:
How much time has passed since the collapse?
Are there any communities nearby that pulled together to form a polity?
Regional demographics?

Not trying to bash your scenario, but one needs SA to make good decisions. Even the question you posed above could be affected greatly by these three, which came off the top of my head, just now. Details are important.