How about going back to basics, and instead of choosing a historical culture, we simply play a primitive culture without reference to any particular historical example?
Take a name like "Grimskeggr" for example. That's clearly Norse. But after translating what the name actually meant to the Norse back then, "Wildbeard" could be a name from any primitive culture, from Norse to Celtic to Native American. That way, we don't have to alienate people.
I would suggest a history that allows diversity. Perhaps we were many distinct but equally primitive and war-like peoples who once lived in the choice lands of Realm Alpha, until their untrustworthy "diplomacy" divided us up and their cowardly "organisation" and "discipline" on the battlefield allowed them to beat us individually. Pushed from our fatherlands, we all fled in the same direction. Now we have our internal disagreements, but we vow that when fighting the Alphans, we will never allow them to trick us again.