Paladin of Souls by Lois McMaster Bujold

Follow Lois McMaster Bujold, one of the most honored authors in the field of fantasy and science fiction, to a land threatened by treacherous war and beset by demons -- as a royal dowager, released from the curse of madness and manipulated by an untrustworthy god, is plunged into a desperate struggle to preserve the endangered souls of a realm.