Board Thread:General Discussion/@comment-26569765-20160409175925/@comment-27213286-20160413224142

The churches, bishops, friars, etc. could be those of the Greek mythology religion. When characters say He or God instead of Gods they could be talking to/about only one God, like just Apollo, Ares, Zeus, Hades, Hephaestus, Dionysus, Poseidon, or Hermes. Doesn't mean they don't believe in other Gods, just that only one of them are relevant to what the character is saying. I don't see enough evidence to say that there is any other religion in Once other than the Greek mythology religion.