Battle of Magh Rath

Battle of Moira

Date	24 June 637
Location	Near Moira, Ulster
Result	Victory for Domnall II

Belligerents

Domnall II's forces

Forces of Congal Cáech; over-kingdom of Ulaid
petty-kingdom of Dál Riata

Commanders and leaders

Domnall II of Ireland

Congal Cáech, king of Ulaid †
Domnall Brecc, king of Dál Riata

Strength

Unknown

Casualties and losses

~Unknown casualties

The Battle of Moira, known archaically as the Battle of Magh Rath, was fought in the summer of 637 by the Gaelic High King of Ireland Domnall II against his foster son King Congal of Ulster, supported by his ally Domnall the Freckled (Domnall Brecc) of Dalriada.

The battle was 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.

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 Dalriada, which had come over from Scotland to occupy a substantial swathe of territory to the north of Lough Neagh. 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, Dalriada, 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 Dalaradia, where he became King, before being recognised as King of Ulster 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 clan) in a previous battle.

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