In Irish origin legends, Míl Espáine or Míl Espáne (later Latinized as Milesius; also Miled/Miledh) is the mythical ancestor of the final inhabitants of Ireland, the "sons of Míl" or Milesians, who represent the vast majority of the Irish Gaels. His father was Bile, son of Breogan.
His name is an Irish version of Latin Miles Hispaniae, meaning "Soldier of Hispania", which is attested in a passage (§ 13) in the 9th-century semi-historical work Historia Brittonum ("The History of the Britons"). The work offers an account of how Ireland was successively taken by settlers from Spain, among them Partholom, Nimeth and the "three sons of a Hispanic soldier" (tres filii militis Hispaniae). As A.G. van Hamel has suggested, the status of Iberia as the land of origin can be traced back to Isidore of Seville, who in the introduction to his history of the Goths, Vandals and Suebi had elevated Spain to the "mother of all races". A further explanation may lie in the mistake made by some classical geographers in locating Ireland closely opposite Iberia. For instance, the Lebar Gabála (§ 100) recounts that from Bregon's Tower, the Milesian Íth was able to see right across the sea to Ireland.
He served as a soldier in Scythia and Egypt, before remembering a prophecy that his descendants would rule Ireland. He set off to the west, getting as far as Iberia where he fought several battles before dying, never seeing Ireland himself.
His wife Scota and his uncle Íth, who had spied Ireland from a tower, sailed to Ireland where Íth was killed by the Tuatha Dé Danann. When his body was brought back to Iberia, Míl's eight sons and Íth's nine brothers invaded Ireland and defeated the Tuatha Dé Danann.
He figures prominently in the mythological genealogies of John O'Hart, being the common ancestor of all the Irish.
Milesius died in Spain before he could reach the Isle of Destiny. His wife Scota went to Ireland with their eight sons. Due to some terrible storms, (attributed to the magic of the Tuatha Dé Danann who already lived in Ireland) most of Milesius' sons died when they tried to land.