Damar Series by Robin McKinley

This is the story of Corlath, golden-eyed king of the Free Hillfolk, son of the sons of the Lady Aerin.And this is the story of Harry Crewe, the Homelander orphan girl who became Harimad-sol, King's Rider, and heir to the Blue Sword, Gonturan, that no woman had wielded since the Lady Aerin herself bore it into battle.And this is the song of the kelar of the Hillfolk, the magic of the blood, the weaver of destinies...

Aerin could not remember a time when she had not known the story; she had grown up knowing it.It was the story of her mother, the witchwoman who enspelled the king into marrying her, to get an heir that would rule Damar; and it was told that she turned her face to the wall and died of despair when she found she had borne a daughter instead of a son.Aerin was that daughter... moreAerin could not remember a time when she had not known the story; she had grown up knowing it.It was the story of her mother, the witchwoman who enspelled the king into marrying her, to get an heir that would rule Damar; and it was told that she turned her face to the wall and died of despair when she found she had borne a daughter instead of a son.Aerin was that daughter.But there was more of the story yet to be told; Aerin's destiny was greater than even she had dreamed--for she was to be the true hero who would wield the power of the Blue Sword... less