Myths of the Norsemen: From the Eddas and Sagas

In mediæval times, the will-o’-the-wisps were known in the North as elf lights, for these tiny sprites were supposed to mislead travellers; and popular superstition held that the Jack-o’-lanterns were the restless spirits of murderers forced against their will to return to the scene of their crimes. As they nightly walked thither, it is said that they doggedly repeated with every step, “It is right;” but as they returned they sadly reiterated, “It is wrong.”