Ah, a good question. The ethnicities will in fact stay the same (maybe some tweaks to spelling), even though we can't really push the tribes back that far in time. After all, by say 100 BC many of the tribes known to the Romans probably already existed, and possibly much sooner. If you like, think of the ethnic identities as being the names of family groups that would later develop into larger tribes - which is precisely what I think did happen.
Thanks Gustave for the shields, he did a bang up job.
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