Clontarf

Brian Bóramha had been high king of Ireland for twelve years when, in the spring of 1014, the king of Leinster Máel Mórda mac Murchada and the Norse-Irish king of Dublin Sigtrygg Silkbeard rose against him and summoned a great army of Hebridean, Manx, Orcadian and Scandinavian Norsemen to their aid. The combined force assembled at Dublin in late March. Brian's own army — the men of Munster, Connacht, the Uí Néill of the south, and the men of his own Dál Cais — marched up from the south and made camp on the strand at Clontarf, north of the Liffey, opposite the city.

The battle was joined on Good Friday, 23 April 1014. By every contemporary account it was the longest and bloodiest field action ever fought on Irish soil — a hand-to-hand mêlée of axes, swords and short spears that lasted from sunrise until evening tide. Brian, by then in his early seventies and forbidden by the church custom of the day from bearing arms on Good Friday, watched the battle from his tent on a low hill above the strand, attended by his confessor and a few household men.

The high king's son Murchadh commanded the centre of the line. He fell late in the day, killed by Anrad the Norseman in the same blow that killed Anrad himself. Brian Boru's grandson Tairdelbach was found drowned at the river-mouth, swept off the strand by the rising tide. The Norse line broke in the late afternoon; Sigurd of Orkney was killed in the Norse rearguard's stand around his raven-banner; Sigtrygg fled into the city walls. The rout was running on toward Dublin Bridge when a small party of fleeing Norsemen — by the Irish account a Norwegian commander named Bróðir of the Isle of Man — chanced on the king's tent and killed him there. He was reading a psalter, by the tradition; the same tradition has him commit one last blow with his sword.

Clontarf has long been read as the moment that broke Norse political power in Ireland. The truth is more limited — the Norse-Irish coastal towns survived and prospered, and the Hiberno-Norse remained an integrated part of Irish society until the Anglo-Norman conquest a century and a half later. But the high kingship Brian had won by force did not survive him. His body and his son Murchadh's were carried in solemn procession over twelve days from Clontarf to Armagh and buried side by side at the cathedral there. The dynasty Brian founded — the Ó Briain — would rule Thomond for the next six hundred years.