- Why do the non-Roman characters defer to Roman gods? "Jupiter" could just be a generic Common Tongue name for "God", but they often mention Apollo and others as well. Presumably, non-Romans (Thracians, Gauls, Germanic peoples, Syrians) living in Rome have their own religious figures, and being attached to their heritage in other ways (Agron especially attracts notice for this, continuing to speak his own language and prefer his own countrymen), why, even without Roman masters overseeing them, do they continue to refer to Apollo, Diana and the like?
- Small Reference Pools meets Translation Convention? People are more likely to have a general sense of what Apollo, Minerva, Diana, etc. represent than the much more obscure Germanic and other pagan gods, just because they get wider exposure in pop culture and education.
- There's also some slaves who may have been taken much earlier in life, as Crixus implies in Gods of the Arena. They may not be aware of what their people's gods are.
Headscratchers / Spartacus: Blood and Sand