The Northern Lights as Ghost Army

Þingvellir, Iceland

In medieval Icelandic tradition, the Northern Lights were the shields of the Valkyries riding across the sky — but an older tradition, preserved at Þingvellir, describes them as an army of the dead re-enacting their final battle.

The Northern Lights — Aurora Borealis — appear over Iceland approximately sixty nights per year, most reliably in autumn and winter. Their scientific explanation was not established until the 19th century; before that, multiple explanatory traditions existed simultaneously in Iceland. The dominant Norse framework — the Valkyrie explanation, in which the lights are the reflections of armour and shields as the divine battle-maidens ride across the sky — is the one most widely known. But the Þingvellir tradition, documented in the parliamentary records of the Alþingi and in oral accounts gathered from the area around the rift valley, preserves an older explanation. At Þingvellir, the Northern Lights were understood as an army of the dead — specifically the dead of battles fought in the area, which had been a site of legal dispute and occasional violence for the thousand years of the Alþingi's existence. The lights were the dead still fighting: the wheeling and flickering of the aurora interpreted as the movement of shields and weapons in a battle that had no end because death had removed the need for one. The tradition specified that if you whistled at the Northern Lights, they would descend. This prohibition was enforced: whistling outdoors on aurora nights was strongly discouraged in the Þingvellir area. Þingvellir is now a UNESCO World Heritage Site. The aurora over the rift valley, with its combination of geological grandeur and the knowledge of a thousand years of human assembly there, continues to produce the response the tradition described.