A Song for Arbonne — Guy Gavriel Kay

It began with love, both courtly and forbidden, and with kingdoms endlessly opposed, one dominated by male rulers and their male god, the other in which women and their goddess held a share of earthly power. For the Northern mercenary called Blaise, though, it began with the death of a king and a peace treaty that was a betrayal which sent him into a self-imposed exile. His wanderings would bring him to the Kingdom of Arbonne, where the Court of Love made warriors bow to troubadours, and a well-sung ballad was valued as much as a skillfully swung sword. But Arbonne was a troubled realm, torn by an ancient feud between its most powerful dukes, and coveted as a prize by the land in which Blaise himself had grown to manhood. And no one--except perhaps Arbonne's goddess--could foresee that one Northern mercenary might become the key to Arbonne's destiny....