Sir Aldingar is Child ballad 59. Francis James Child collected three variants, two fragmentary, in The English and Scottish Popular Ballads. All three recount the tale where a rebuffed Sir Aldingar slanders his mistress, Queen Eleanor, and a miraculous champion saves her.
Various forms of the legend it recounts have been recorded in many ballads, romances, and sagas. Although many have been recounted as historical accurate, no evidence supports any such claims.