Brian Boru

Brian Borumha, King of Ireland, a descendant of Oilill Olum, was born about 941.

His brother Mahon succeeded to the throne of Munster in 951.

The Northmen then occupied much of the dominions of his ancestors, their discipline and ferocity bearing down all before them.

Mahon succumbed, and entered into a treaty with them; but Brian, although a lad, headed a small band of warriors in opposing their advances.

Eventually there was a general gathering of the Irish clans, headed by Brian and Mahon.

The Danes were defeated at Sulcoit, near the town of Tipperary, in 968, and Mahon and Brian entered Limerick, where they took much spoil and a large number of prisoners.

Nevertheless it was not long before the invaders were again permitted to occupy the town as traders.

About the year 976, Ivar, lord of Limerick, and Molloy, son of Bran, who had been expelled from Desmond, compassed Mahon’s assassination.

Brian immediately ascended the throne of Thomond; he attacked and slew Mahon’s murderers—Ivar and his two sons, and Donovan their Irish ally.

Two years afterwards he fought the battle of Bealachlechta, in which fell Molloy, King of Desmond, and Brian found himself master of all Munster.

In 982, while he was upon an expedition ravaging Ossory, his dominions were invaded by Malachy Mor, King of Ireland, who cut down the sacred tree at Adair, under which Brian and his ancestors of the Dalcassian line had been crowned.

In 984 Brian revenged this outrage by plundering Westmeath; whereupon Malachy again turned his arms against Thomond, and defeated the Dalcassians with a loss of 600 men, including Brian’s uncle.

In 993 Brian prepared a fleet of boats, sailed up the Shannon, and invaded Leitrim and Cavan.

Before long, however, the renewed successes of the Danes obliged Brian and Malachy to lay aside their feuds and unite against the common enemy.

After preliminary operations, in the year 1000 they fought the Danes at Glenmama, near Dunlavin, in the County of Wicklow; great slaughter ensued on both sides.

The foreigners were defeated; 4,000 of the Danes of Dublin were slain, with their chiefs Harold, and Cuilean son of Echtighern.

“The victorious army seems to have met no opposition on their way to Dublin, where they immediately made themselves masters of the fortress. Here spoils of great value were found; great quantities of gold, silver, bronze, and precious stones, carbuncle gems, buffalo horns, and beautiful goblets, as well as vestures of all colours. Brian and his army, we are told, made slaves and captives of many women, boys, and girls; and this is defended as being a just retaliation upon the foreigners, who were the first aggressors, having come from their home to contest with the Irish the possession of their own country and lawful inheritance.”

For the next two months Brian made Dublin his head-quarters.

After a time he received Sitric, the Danish king, into favour, and re-established him as King of Dublin.

The time now appeared suitable to Brian for the accomplishment of designs he long contemplated.

Clear-sighted and resolute, he had, by the glory of his achievements and the policy of his alliances, undermined the authority of Malachy. He thereupon marched to Tara, and demanded Malachy’s submission.

Malachy craved a month’s time for consideration. At the end of this period, unsuccessful in his efforts to obtain assistance (even his kinsmen—princes of Ulster and Connaught—coldly holding aloof or demanding an exorbitant price for their assistance), Malachy formally submitted, and then acknowledged Brian as King of Ireland (1002).

Brian proved himself worthy of his position, and but for his death at Clontarf, might have permanently consolidated the Irish power.

We are told that roads, bridges, schools, sprung up under his rule, and that education and the arts of peace began to flourish.

We read of his offering twenty ounces of gold on the altar at Armagh; and his name, inscribed in his presence, may yet be read in The Book of Armagh, preserved in Trinity College.

His yoke was peculiarly galling to the Danes, who had been able to extend their sway over England and other parts of Europe.

There was also latent dissatisfaction among the minor Irish princes.

The spark to kindle the flames of war among such combustible materials came from Maelmordha, King of Leinster, who received a fancied insult at Kincora, Brian’s palace near Killaloe, from the hands of Murrough, son of Brian, over a game of chess.

His anger was increased by some insulting remarks on his supineness under Brian’s yoke, passed by his sister Gormlaith, Brian’s third wife, said to be the most beautiful woman in Ireland at the period.

A league was formed against Brian, and the preparations made for a contest evinced how much depended on the issue.

The Northmen summoned to their aid all of their nation in Ireland who could possibly attend; they also sent to Denmark for reinforcements; and the Orkneys and Hebrides furnished contingents.

To these were added the forces of Leinster under Maelmordha, Dunlaing (ancestor of the O’Tooles), and Brogarbhan, tanist of Offaly—indeed of all the country east of the Nore and Barrow, and south of the Liffey.

To meet this array, Brian and Malachy marshalled the forces of Munster and south Connaught, with levies from the Eoganachts of Scotland.

The two armies, of about 20,000 each, met at Clontarf on Good Friday,the 23rd of April 1014.

“Few particulars of this remarkable battle have descended to us deserving of being set down as true history. That a great and decisive victory was gained by the Irish troops is undoubted. That it was attended with severe loss to the victors is equally certain. … If to the 4,000 Danes, who are thus included in the slain, we add the 3,000 of the Leinster troops, it will render highly probable the correctness of the estimate of the Ulster annalists, that the whole loss on the side of the Danes did not exceed 7,000. The loss on the part of the Irish leaders is nowhere stated. … There fell of the monarch’s family, himself, his eldest son Murrough, Turlough, son of Murrough, a youth of fifteen years of age, and who was, according to the Annals of Clonmacnoise, “found drowned near the fishing weir of Clontarf, with both his hands fast bound in the hair of a Dane’s head, whom he had pursued to the sea at the time of the flight of the Danes,” and last, Conaing, nephew to Brian.”

Besides minor chiefs, about twelve great Irish leaders fell.

The following particulars of Brian’s death are given in the account of the battle and of the names of the slain, in The Wars of the Gaedhill with the Gaill.

Brian had retired to his tent in the middle of the engagement to pray:

“The attendant perceived a party of the foreigners approaching them. The Earl Brodar was there, and two warriors along with him. ‘There are people coming towards us here,’ said the attendant. ‘Woe is me, what manner of people are they?’ said Brian. ‘A blue stark naked people,’ said the attendant. ‘Alas!’ said Brian, ‘they are foreigners of the armour, and it is not to do good to thee they come.’ While he was saying this, he arose and stepped off the cushion, and unsheathed his sword. Brodar passed him by and noticed him not. One of the three who were there, and who had been in Brian’s service, said—‘Cing, Cing,’ said he, ‘this is the King.’ ‘No, no, but Priest, Priest,’ said Brodar, ‘it is not he’ says he, ‘but a noble Priest.’ ‘By no means,’ said the soldier, ‘that is the great King, Brian.’ Brodar then turned round, and appeared with a bright, gleaming, trusty battle-axe in his hand, with the handle set in the middle of it. When Brian saw him, he gazed at him, and gave him a stroke with his sword, and cut off his left leg at the knee, and his right leg at the foot. The foreigner dealt Brian a stroke which cleft his head utterly; and Brian killed the second man that was with Brodar, and they fell both mutually by each other. There was not done in Erinn, since Christianity, excepting the beheading of Cormac MacCuilennain, any greater deed than this. In fact he was one of the three best that ever were born in Erinn, and one of the three men that most caused Erinn to prosper. … For it was he that released the men of Erinn, and its women, from the bondage and iniquity of the foreigners, and the pirates. It was he that gained five and twenty battles over the foreigners, and who killed and banished them, as we have already said.”

Brian was aged about 73 at the time of his death.

After the battle, his body and the bodies of the other members of his family slain, were carried to the monastery of St. Columcille at Swords, where they were received by the Bishop of Armagh and his clergy, and carried to Armagh, where they lay in state for twelve nights, after which they were interred in a new tomb.

The general adoption of surnames in Ireland is supposed, perhaps erroneously, to have first taken place in Brian’s reign—Mac being prefixed for son; Ua or O for grandson; Ni, daughter or grand-daughter.

Brian’s annual revenues are stated to have been:—Connaught, 800 cows and 800 hogs; Tirconnell, 500 cloaks, and 500 cows; Tirowen, 60 hogs, and 60 loads of iron; Ulster, 150 cows, and 150 hogs; Oriel, 160 cows; Leinster, 300 cows, 300 hogs, 300 loads of iron; Ossory, 60 cows, 60 hogs, 60 loads of iron; the Danes of Dublin, 160 hogsheads of wine; the Danes of Limerick, 365 hogsheads of red wine. The proportions contributed by Munster are not specified.

Brian derived his cognomen of “Borumha” from the Borromean tribute he exacted from Leinster—a tax that had lain in abeyance since the year 694.

The battle of Clontarf was decisive as regards Danish supremacy in Ireland. Nevertheless the Danes continued to occupy most of the sea ports until the Anglo-Norman invasion.

After Brian’s death, Malachy resumed the supreme power.

For Brian’s descendants, see O’Brien.


134. Four Masters, Annals of Ireland by the: Translated and Edited by John O’Donovan. 7 vols. Dublin, 1856.

144. Gaedhil with the Gaill, Wars of the, or the Invasions of Ireland by the Danes: Rev. James H. Todd, D.D. (Master of the Rolls Series.) London, 1867.

171. Ireland, History of, from the earliest period to the English Invasion: Rev. Geoffrey Keating: Translated from the Irish, and Noted by John O’Mahony. New York, 1857.

263. O’Briens, Historical Memoir of the: John O’Donoghue. Dublin, 1860.