Finding names endemic to a region

[Zero Day Defense]

I was curious about old (pre-Christian) European names, but-- especially outside of Celtic names-- every time I find a list, nearly all the names are derived from Latin, or from Latin through Greek. Essentially, they're Christian names. Even when they're labeled as having a Danish origin (for example), just a bit more research indicates that it's just a variant of a Latin/Latin-from-Greek name.

Where can I go to find the kinds of names I'm looking for without being bamboozled?

 

[BlueSpark]

Go on Wikipedia and look up the history of countries before Christian conversion and look at the names of rulers eta.