 In "The Lord of the Rings", Rohan is important in the action, first against the wizard Saruman in the Battle of the Hornburg, and then in the climactic Battle of the Pelennor Fields.There, Théoden leads the Rohirrim to victory against the forces of Mordor; he is killed when his horse falls, but his niece Éowyn kills the leader of the Ringwraiths.Tolkien's own account, given in "The Letters of J. R. R. Tolkien", No.