Editing Provinces of Ireland (section)

===The Three Collas and the founding of Airgíalla===
The main body of the events in the myth of [[the Three Collas]] may have occurred in the late 4th to early 5th century; however, as the centuries passed the myth underwent updating and alteration.<ref name="Schlegel160-4"/> The most oft quoted version of their story was written by Geoffrey Keating in the 17th century in his work the {{lang|ga|[[Foras Feasa ar Éirinn]]}}, also known as "The History of Ireland".<ref name="Schlegel160-4"/>

In it the Three Collas—Colla Menn, Colla Da Crioch, and Colla Uais—were the sons of Eocaidh Doimlén.<ref name="Schlegel160-4"/> It is from them that the Airgíalla are said to descend, branching off from the rest of the Connachta.<ref name="Schlegel160-4"/> The Northern and Southern Uí Néill dynasties are claimed to descend from Eocaidh's brother, [[Fiacha Sraibhtine]].<ref name="Schlegel160-4"/> According to the story the Collas were told by Fiacha's son, [[Muiredach Tirech]], the High King of Ireland, to conquer land of their own to pass on to their descendants, directing them to wage war on the Ulaid to avenge a slight against their great-grandfather [[Cormac mac Airt]].<ref name="Schlegel160-4"/>

The Collas with their army along with a host from Connacht marched to [[Achaidh Leithdeircc]] in Fernmagh, southern Ulaid, and fought the Ulaid in seven battles over the course of seven days.<ref name="Schlegel160-4"/> The host from Connacht fought the first six battles, and the Collas fought the seventh.<ref name="Schlegel160-4"/> It is after this last battle that the king of Ulaid, [[Fergus Foga]], was killed and his army routed.<ref name="Schlegel160-4"/> The Collas then pursued the Ulaid east of the "Glen Righe" (the valley of the [[Newry River]] in eastern County Armagh), before returning to loot and burn the Ulaid capital, Emain Macha, after which it never again had a king.<ref name="Schlegel160-4"/> They then took possession of central Ulaid spanning the modern counties of Armagh, Fermanagh, Londonderry, Monaghan and Tyrone founding the over-kingdom of Airgíalla.<ref name="Schlegel160-4"/>