Erris in Mayo was the scene of the landing of the chief colony of the Firbolgs, and the battle which is said to have resulted in the overthrow and almost annihilation of this tribe took place also in this county, at Moytura near Cong.
This third body of invaders is known collectively as Firbolgs, and is ethnologically and historically very important.
Many authorities such as Keating and MacFirbis admit that descendants of the Firbolgs were still to be found in parts of Ireland in their own day, though they are characterized as " tattling, guileful, tale-bearing, noisy, contemptible, mean, wretched, unsteady, harsh and inhospitable."
The Firbolgs had scarcely established themselves in the island when a fresh set of invaders appeared on the scene.
Eochaid, son of Erc, king of the Firbolgs, having declined to surrender the sovereignty of Ireland, a great battle was fought on the plain of Moytura near Cong (Co.
In this contest the Firbolgs were overthrown with great slaughter, and the remnants of the race according to Keating and other writers took refuge in Arran, Islay, Rathlin and the Hebrides, where they dwelt until driven out by Picts.
Subject or plebeian tribes, or in other words the Firbolgs, who paid daer- or base rent to the Milesians.
In the early centuries of our era Ireland would therefore have been occupied by the Firbolgs and kindred races and the Milesians.