Welcome to the org Delig!
Thermon is already in the campaign, as is the oracle at Delphi, which appears as a building in Thermon. I think it does give morale bonuses already.
@Geoffrey: because Greece's history is quite famous amongst most people, as are many of her city states, and not all people are interested in and read about classical history. Greek myths, being so well known, also help in giving most people the impression that Greeks were very influential (which they were) and therefore powerful.
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