So for Hrothgar, based on the random generator they appear to be highly influenced by Slavic names. Like, most of the first names are legit actual Slavic names. The Helions last names seem to be A+{name} (although most of the names that they use in the random generator are female) and The Lost have {name}+sch.

The wikipedia page is a good resource for examples.
https://en.wikipedia.org/wiki/Slavic_names

FWIW Mir-/-mir meaning peace and Slav-/-slav meaning glory/fame/celebration are super common roots.

I couldn't tell you for Viera I'm afraid.