Parthenia was a northern province of Detina. It went with 'King' Geoffrey and became a battleground during the Detinan Civil War, defended by Duke Edward of Arlington and attacked by Marshal Bart. It was where Duke Edward and Doubting George hailed from. Parthenia was defended staunchly because it was where King Geoffrey's capital of Nonesuch was situated and because it was one of the north's most valuable and leading provinces.