Lebor Gabála Érenn is a collection of poems and prose narratives in the Irish language intended to be a history of Ireland and the Irish from the creation of the world to the Middle Ages. There are a number of versions, the earliest of which was compiled by an anonymous writer in the 11th century. It synthesised narratives that had been developing over the foregoing centuries. The Lebor Gabála tells of Ireland being settled six times by six groups of people: the people of Cessair, the people of Partholón, the people of Nemed, the Fir Bolg, the Tuatha Dé Danann, and the Milesians. The first four groups are wiped out or forced to abandon the island; the fifth group represents Ireland's pagan gods, while the final group represents the Irish people.

Nemed or Nimeth is a character in medieval Irish legend. According to the Lebor Gabála Érenn, he was the leader of the third group of people to settle in Ireland: the Muintir Nemid, Clann Nemid or "Nemedians". They arrived thirty years after the Muintir Partholóin, their predecessors, had died out. Nemed eventually dies of plague and his people are oppressed by the Fomorians. They rise up against the Fomorians, attacking their tower out at sea, but most are killed and the survivors leave Ireland. Their descendants become the Fir Bolg.