The Gaels are the descendants of Fenius Farsaid, Goidel Glas, Lamfhind, and Mil Espaine, and the final group to settle in Ireland, replacing the Tuatha de Danann. Compared to other invaders of Ireland, such as the Danann, or the Fir Bolg, the Gaels migrated a lot. They originated in Scythia, then moved to Egypt (the birthplace of Goidel Glas), then back to Scythia, then to Gotland, then to Spain, and finally, to Ireland.

To see how and why the Gaels invaded Ireland, see Milesians.