The Annals of Ulster, the earliest and most reliable of the ancient annals that survive, tell us simply that 'the battle of Achad Leithderg in Fernmag' happened 4,334 years after the creation. Achad Leithderg has not been identified but Fernmag was (at the time of the annalists) roughly the Monaghan valley. Under the yeare 331 A.D., we read 'The battle of Achadh leithderg in Fernmagh was fought by the three Collas against the Ulaid in which fell... the last king of the Ulaid at Emhain. They afterwards burned Emhain, and the Ulaid did not dwell there since. Emain Macha was Conchobar's capital - the seate of power in Ulaid (Ulster), the place now being known as Navan Fort near Armagh.
Macha was a daughter of Áed Ruad, a prince of Ulaid (Ulster). Áed Ruad was either a brother or cousin to Dithorba and Cimbáeth (Kimbay), whom Áed Ruad shared the kingship of Ulaid. The name Macha appeared several other times before she appeared as daughter of Áed Ruad. The name first appeared as wife of Nemed, leader of the Nemedians. Macha appeared again, as the wife of Nuada, king of Ireland and leader of the Tuatha Dé Danann. Macha and Nuada died in the Second Battle of Mag Tuired. The Danann Macha was identified as the Irish goddess of fertility, war and of horses. Macha was one of the aspects of Morrígan (Morrigan). As goddess of horses, Macha was the Irish equivalent of the Gallic horse-goddess Epona and the Welsh goddess Rhiannon. She reappeared in the Ulaid Cycle as wife of Crunnchu and was associated with the curse placed upon the men of Ulster. According to the Irish custom, the heir to the throne was not the eldest son, but the member of the royal family, or royal blood, who was adjudged most worthy. This gave a constant pretext to rival claimants. And the enemy abroad was ever on the watch. The Kinel-Owen were ready at all times to take advantage of Uladh's difficulty or temporary weakness. As years went on, the King of Uladh, who had at first aspired to regain his lost sovereignty over Ulster, found himself at length unable to hold his power over his tributary kings and princes. Tír na nÓg
CREW HILL came into prominence in Irish history after the destruction of EMANIA, in 335 A.D. Up to that time Emania was the centre of royal power for the whole Province of Ulster. Its King, according to the Book of Rights, had the privilege of sitting by the side of the King of Erin, and held first place in his confidence. The Palace of Emania yielded in fame and magnificence only to the Palace of the High-King at Tara. At the dawn of history it had a storied past from the Milesian Ir. It had been founded by Queen Macha of the Golden Hair three centuries before the Christian era. It reached its highest glory in the time of Conor Mac Nessa and his Red Branch Knights.
ARD MACHA, or Hill of Macha, from an ancient queen, one of three bearing that name said to be buried on the hill now crowned by the old cathedral. In 352 B.C, the seate of the kings and queens of Ulster, it lasted for 700 years and was destroyed in the fourth century A.D.[Clanna-Daimhin in Oirghialla]. About one hundred years later, the foundation of Armagh as a town followed the arrival of St. Patrick; Daire, the chieftain of the district, provided a site for a church. An important synod was held at Armagh in or about 448, and it is also reported that Armagh was a renowned seate of learning in the Dark Ages. There, the Bishops of Armagh retired to Drogheda.
The confluence of the River Blackwater (flowing south east from Virginia Lake and the famous River Boyne) occurs in Navan. Situated in the famous Boyne Valley the town is close to Brú na Bóinne (the Neolithic monuments of Newgrange, Knowth & Dowth), the Hill of Tara, Skryne and Slane, as well as the heritage towns of Kells and Trim.