E. Phillips Oppenheim 
The Traitors 

The tiny kingdom of Theos is surrounded by Eastern European powers in this 1902 novel of politics, war, and romance. Russia and Turkey are plotting to take over the peaceful and rural country. A short lived Republic has been treacherously betrayed by communist elements. The country turns to its exiled King, Ughtred of Tyrnaus, a prince who has been a soldier in Britain for twenty years. The prince is convinced by Baron Nicholas of Reist to return to Theos and be crowned. Continuous action, changing alliances, loyalty and betrayal are all in play.