Battle of Moira (Mag Rath) 637
Who Fought
Approximately 50,000 men on either side, totalling around 100,000 combined, according to the sources. The Dal Riata force included Scots, Picts, Anglo-Saxons and Britons.
History & Significance
The Battle of Moira, also known as the Battle of Magh Rath, was fought in the summer of AD 637 by the High King of Ireland, Domnall II, against his foster son Congal Cáech, King of Ulaid, supported by his ally Domnall Brecc, King of Dál Riata. The battle resulted in a decisive victory for the High King and his army, and Congal Cáech was killed in the fighting.
The battle was reputedly fought near the woods of Killultagh just outside the village of Moira in what would become County Down. It was allegedly the largest battle ever fought on the island of Ireland, and resulted in the death of Congal and the retreat of Domnall Brecc. However, the location of the battle is not settled and some commentators identify the location as being a few miles outside Newry, County Down in the vicinity of the townlands of Sheeptown and Derrylecklagh near to the ancient rath known as the Crown Mound.
Ireland in the period was a patchwork of petty statelets, fused together and driven apart by tribal loyalties, often given to a state of war. Other realms from across the water in Great Britain and in particular Scotland frequently became involved in the affairs of Ireland, notably the Scottish branch of Dál Riata, which had originally been from north of Lough Neagh but expanded across to Scotland. Indeed, the tribal loyalties often spilled across the Irish Sea, where the same clans could be found on either side, especially in Scotland. Rivalries and alliances between the petty kingdoms changed frequently. For example, Dál Riata, which fought with Congal in this battle, had seen one of their kings killed by his brother at the Battle of Fid Eoin (either 629 or 630).
Congal himself had first established his power base in Dál Riata, where he became King, before being recognised as King of Ulaid in 627. His ambitions soon came into conflict with Domnall II, who became High King of Ireland in 628. Ironically, Domnall II only rose to such a position because Congal had defeated and killed the previous High King, Suibne Menn, (who was Domnall's distant cousin in the Uí Néill dynasty) in a previous battle.
Domnall at first launched a raid into Leinster in 628 to secure his authority as High King. Some primary sources state that Congal had initially become the Ard Rí following his defeat of Suibne Menn. It may be therefore that Domnall seized the position indirectly from his Ultonian rival. Regardless, the two had become enemies.
Domnall pressed this rivalry very quickly, and in 629 the two kings engaged each other at the Battle of Dún Ceithirn in what is now County Londonderry. On this occasion Congal was defeated and fled to Scotland to seek support, and Domnall was left unchallenged as the High King.
The ground they fought on
The site of Battle of Moira (Mag Rath) 637 lies on Unnamed Extrusive Rocks, Palaeogene, bedrock that formed in the Paleogene. The rock here is mafic lava and mafic tuff.
The most arresting confirmation of the battle's legendary scale came not from any medieval manuscript but from the navvies of the nineteenth century. When the Ulster Railway was being constructed through Moira, the excavations turned up the remains of thousands of men and horses buried in the ground beneath the townland. Given that the survivors of such a battle would have carried off many of their dead and that great numbers escaped the field entirely, the sheer volume of skeletal remains uncovered by the railway works gave compelling physical witness to the ancient tradition that this was the largest battle ever fought on the island of Ireland.
Frequently Asked Questions
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- Battle of Moira · Wikipedia
- Dál Riata · Wikipedia