King Olaf

King Olaf is the ruler of one of the five kingdoms, that's name remains unknown. His beautiful daughter, Lady Vivian, is the apple of his eye, and he is ridicously protective of her. Vivian even told Arthur that the king chased one her former lovers with a knife. He and his daughter appear in Sweet Dreams, where Arthur and Vivian are enchanted to fall in love with each other...which isn't very good for either because when Olaf finds out, he challenges the prince to a fight to the death! Arthur ends up winning, but he doesn't kill Olaf, saying that that isn't the way to make peace.

Vivian is rumoured to be returning in Season 4, meaning King Olaf might, too.