Celtic mythology - the first
mythological invaders of
Ireland, whose name means "under demons", led by their king,
Balor, who had a single eye the glance of which could strike an army dead. This fearful weapon was controlled by Balor's assistants, who raised and lowered his eyelid at need.
Ireland was invaded next by the Tuatha De Dannan, led by Nuada, who lost his arm in battle. Because kingship demanded physical perfection, he was succeeded by Bres, whose father was a Fomor. Bres' reign became increasingly oppressive, and Nuada was encouraged by Lugh to seek the overthrow of Bres. Nuada was fitted with a silver arm in order to seek the kingship once more.
War ensued between the Fomorians and the Tuatha De Danan. The first Battle of Magh Tuiredh was long, fearsome and bloody. Baor was killed by a slingstone cast by Lugh, driving his eye back in his head so his gaze fell upon his own army.
Most references to the Fomorians are to darkness in opposition to the light of the Tuatha De Dannan.