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When most people hear of the ‘Norman invasion,’ they instantly think of Duke William’s invasion of England in 1066. There were, however, actually four identifiable Norman conquests. The first and original invasion was the conquest of the area in France that later came to be called Normandy, named for the Norsemen who carried out the invasion. Second, and according to some people the most historically important and influential, was the Norman conquest of southern Italy and Sicily. That began in 1016, a full half century before the invasion and subjugation of England by William I and his followers. The fourth and final invasion was the Anglo-Norman invasion and partial conquest of Ireland, which began in 1169 at the invitation of Diarmuid Mac Murchada, king of Leinster, under the auspices of King Henry II of England.

The relative difficulty of the conquests can be estimated by noting the length of time it took for each undertaking to be completed. William’s conquest of England was effectively accomplished in part of one day. It was more than three-quarters of a century before Norman control was firmly established over southern Italy and Sicily. The total conquest of Ireland by the Normans was never actually completed–unless the utter devastation during Oliver Cromwell’s campaign of 1649-50 is viewed as an extension of Norman activity. By that time, however, the Normans and Saxons had fused to become the ‘English.’

The invasion of Ireland was apparently the last burst of Norman expansionism and marked the greatest extent of their unofficial empire. At their height, Norman kings, dukes or warlords exerted varying degrees of political control over Normandy, southern Italy, Sicily, England, Wales, parts of what is now Yugoslavia, Turkey and, according to some authorities, small enclaves in the north of Africa, as well as Ireland.

It all began as a somewhat typical Irish internecine fight. The underlying reasons for the success of the Normans in Ireland, however, go back to April 23, 1014. It was on that Good Friday, on the field of Clontarf, that the Irish won a battle and a war–but lost the nation. The unarmored Irish under Brian Bóruma, (modern spelling Boru), himself a noncombatant, fought and defeated the armored Danes, resulting in the elimination of the Danish threat in Ireland. What turned this otherwise stunning success into a Pyrrhic victory was the death of Brian, known as ard righ (high king) and imperator scotorum (emperor of Ireland), along with his son and grandson, before he could adequately centralize the government and appoint a successor. That virtually guaranteed Irish disunity at a crucial time a century and a half later. Although he was himself a usurper of the high kingship, Brian was the first Irish ruler with a practical (albeit flawed) vision of a united Ireland. His personal failure was Ireland’s ultimate failure, and the Normans took full advantage of it.

In 1152, the specific incident occurred that triggered the Norman invasion of Ireland–not that much of a pretext was needed once Henry Plantagenet had decided it was his duty to take possession of the island and add it to the Angevin empire, which then encompassed territory in France as well as England. It was in that year that Dervorgilla, the wife of Tighernan O’Ruarc (modern spelling Tiernan O’Rourke), king of Breffni and East Meath, ran off with Diarmuid Mac Murchada (modern spelling Dermot MacMurrough, also known as the Mac Carty-Murrough), king of Leinster. Opinion seems divided as to whether or not she went willingly, but the evidence suggests that she not only had plenty of opportunities to escape but also connived in the plot herself. In any event, both of the principals should have known better–Dervorgilla was more than 40 years old, and Mac Murchada was over 60. Legend has it that Tighernan O’Ruarc, the lady’s lawful husband, was of uncomely appearance (his nickname was Monoculus, or ‘One-eye’), which might seem a sufficient excuse for his wife running off with another man.

In any event, it took O’Ruarc 14 years to build a power base sufficient to repay the man who had wronged him. He had already regained his wife in 1153 with the help of Ard Righ Turlough O’Connor, but he obviously felt that simply taking back what had been stolen was not enough. While 14 years may seem like a long time to wait for vengeance, the Irish have apparently always agreed with the Sicilians’ belief that revenge is a dish best served cold. There is also the more practical aspect of the matter in that O’Ruarc, as king of Breffni and East Meath, did not control nearly the strength in arms that the king of Leinster had at his command. It was obviously the best strategy, militarily speaking, to wait.

When Mac Murchada’s strong ally in the north, O’Loughlin of Tir-Eoghan, died in 1165, the king of Leinster was weakened to such a degree that it was at last feasible to move against him. A confederacy was formed, headed by Turlough’s successor Ruairí (often Anglicized to ‘Rory’ or ‘Roderick’) O’Connor, king of Connaught and ard righ. He was joined not only by the wronged O’Ruarc but also by the king of the Danes of Dublin and many of the lesser kings and nobles of Leinster who had for years resented the tyranny of their lord.

Yet, although many of the upper classes were antagonistic toward Mac Murchada, most of the common people seemed to hold him in great affection. He was viewed as their protector against the aggression of the ‘men of Erin,’ particularly of the ard righ and his armies. For centuries the Leinstermen had allied themselves with foreign invaders against the rest of Ireland, a pattern that would be repeated with the Normans. In spite of Mac Murchada’s popularity with the common people, however, the ouster was successful, and the king fled to Aquitaine to try and drum up support for a restoration.

Two reasons are generally given as a justification for the Norman involvement, aside from helping some minor king (from the English point of view) regain his throne. One motive was to stop the slave trade between the western coast of England and the eastern part of Ireland. The other was to halt the decay of the Irish church and reform it in order to bring it more into line with the Continental norm.

But an invasion of Ireland would have done little or nothing to halt the traffic in human beings. English slavers sold their own countrymen to the Danes in Ireland, and the practice continued for some time after the conquest had been consolidated. It is generally agreed nowadays that the trade would better have been stopped by carrying out sanctions against those primarily responsible for it–the English.

As to the plausibility of religious motives for the conquest, the holiness of the Irish clergy and the effectiveness of their pastoral care were known throughout the Western world. Saint Bernard of Clairvaux, one of the strictest and most rigorous reformers of the medieval church, was greatly impressed with the Irish priesthood. His best friend was Saint Malachy O’More, primate of all Ireland, who died in Saint Bernard’s arms and was buried in the holy abbot’s own habit. When Saint Bernard’s time came to die, he was in turn buried in the habit of the Irish archbishop. Such an endorsement tends to negate the claim that the Irish church was in need of such drastic reform, although civil and religious order had not fully recovered from the chaos following the Battle of Clontarf.

The only plausible reason for the conquest is virtually the only one remaining–and the only one not generally brought up–Norman hunger for land, for which Ireland seemed to be eminently available.

It is often stated that the Irish were a savage and barbarous people in the 12th century. That description comes largely from Giraldus Cambrensis, the Welsh-born Norman scribe who, like Geoffrey of Monmouth in his History of the Kings of Britain, had a vested interest in representing the Norman invasion as being necessary to the well-being of the people and the improvement of civilization. It was essentially a medieval version of the ‘white man’s burden’ argument of the 19th century. However, Irish art, literature and scholarship were known and valued even in the Byzantine empire. And although the various Irish kingdoms under the ard righ had a large measure of autonomy (especially since Brian Bóruma had failed in his attempt to consolidate power) and were often at war with one another, political stability is not a strong criterion for determining whether or not a people is civilized. Cambrensis is also the source for the idea that the entire nation of Ireland was virtually without religion at that time, but Saint Bernard’s testimony largely contradicts that claim.

In any event, while the exiled Mac Murchada offered to do homage to the English king for his domain of Leinster, he did not immediately succeed in gaining the support and assistance of Henry II. Henry had other fish to fry, but he did issue a declaration of friendship with Mac Murchada and give general permission for any Norman lords and knights who wished to join with him in the venture. After all, while Henry II was notoriously stingy, a piece of parchment cost him nothing, and the declaration might rid him of possible troublemakers by sending them on a foreign campaign. Later, as liege lord, Henry could take possession of any lands gained by his vassals without having risked any of his own army or spent any of his own money. He had nothing to lose.

Mac Murchada then went to Wales, where he managed to find two men willing to give him material aid–Rhys, prince of South Wales, and Richard de Clare, earl of Striguil and Pembroke, known to history as Strongbow. The motives of the two men were similar. The Norman-Welsh prince had to deal with a great many landless relatives and vassals, and he needed some kind of outlet for them and a way to establish them without draining his purse. Red-haired Strongbow, whose arms reached to his knees, was in debt over his head and fleeing from creditors. Again, Ireland seemed a perfect solution.

Despite his seemingly effeminate manners, Strongbow was actually a man of great courage and resourcefulness. Readily accepting the proposals of the dispossessed Irish monarch, he agreed to gather a force of volunteers sufficient to replace Mac Murchada on his throne. For his part, the Irish king, upon the success of the venture, was to give Strongbow the hand of his daughter, the beautiful Princess Aoife (usually Anglicized to ‘Eva’), and the succession of his kingdom when he should die–something that was not Mac Murchada’s to promise.

Mac Murchada returned to Ireland with a small personal Norman-Welsh guard–and probably to popular acclaim from the people of Leinster. He was permitted to stay on the condition that he get rid of his escort, agree to bring no more foreigners into the country, and go into immediate seclusion at the monastery of Saint Madog. He complied at once, having no scruples about negotiating an agreement that he had already made plans to break.

Early May in the year 1169 marked the first Norman incursion into Ireland. As Strongbow was in disfavor with Henry II, he sent some of his close relatives until he should obtain the English king’s express permission to take part in the expedition. The aid supplied turned out to be all that was needed to carry out the agreement and restore Mac Murchada to the throne of Leinster. Unfortunately for Ireland, the Normans had a somewhat more ambitious program in mind.

A force of 30 knights in full armor, 60 horsemen in half armor and 300 Welsh archers, led by Robert FitzStephen (Strongbow’s half brother), and another force of 300 men at arms, mostly Flemish mercenaries, led by Maurice de Prendergast, landed at Bannow Creek, south of Wexford, and camped on an island there. When Mac Murchada heard the news of their landing, he quickly assembled 500 of his former subjects and hurried to meet them.

While an army of 1,200 men may not seem very large today, it was for its time a most efficient and effective fighting force, particularly noteworthy for the soldiers’ discipline and relatively modern arms, which dramatically increased their effectiveness. Even without modern arms, training, discipline and morale can produce a victory against disproportionate numerical odds.

It was not want of courage that would lead to the Irish defeat, but the training, skill and discipline of the invaders, combined with their strange appearance. When Mac Murchada appeared with his foreign allies before the Norse-Irish city of Wexford, the Irish quickly retreated behind the walls at the sight of armored men and horses.

At that time, the Irish fought either unarmored or used old-fashioned scale armor. They did not usually fight from horseback, and when they did, they rode bareback because stirrups had not yet been introduced into Ireland. The weapon most commonly used was the ax, supplemented with the short Irish spear–hardly the equals of Norman chain mail and swords. It would not be until the Irish developed an early version of the hedgehog formation, using shields and longer spears, that they would be able to stand against armored cavalry.

After enduring two days of continuous assault against the walls of Wexford, the Irish capitulated and again acknowledged Mac Murchada as their lord. As the restoration seems to have been supported by a popular rising, the nobility probably had little choice. Ossory was conquered in short order, leaving Mac Murchada once again in full possession of the kingdom of Leinster. He granted lands along the coast between Wexford and Waterford to his Norman allies, and it appeared that the project had reached its completion without the Earl of Pembroke–the man later given sole credit for the victory–ever having left England.

The return of the obnoxious king of Leinster–made even more distasteful to the rest of Ireland by the fact that he had dragged in foreigners and made them permanent residents–was not to be countenanced by the ard righ, however. Mac Murchada also seemed to have lost a great deal of his personal popularity with the common people of his kingdom–something that he managed to lose completely in the next year. Ruairí O’Connor assembled a large army and prepared to move against Mac Murchada. Before the campaign began, however, Ruairí reached an agreement with the reinstated king that permitted Mac Murchada to remain in possession of Leinster if no more foreign mercenaries were brought into the country. This was not as cowardly an act as it seems, although the ard righ was not to be remembered for his decisive actions. Ruairí simply recognized that his Irish levies, however impressive their spirit and courage, were no match for the Normans.

No sooner had the agreement been reached, however, than more Normans arrived. Mac Murchada promptly sent them against Dublin to avenge his father’s murder many years before. Dublin surrendered after suffering heavy losses.

Then Mac Murchada became even more ambitious. Having regained his kingdom, obtained his revenge and gathered spoils from the sacking of Dublin, he now judged himself fit to be ard righ–with the help, of course, of his Norman allies. He sent word to Strongbow to come and assist him as promised.

Strongbow landed north of Waterford in August 1170, with as many men as were already in Ireland under the Normans. Waterford fell almost immediately, and the combined forces of Mac Murchada and Strongbow then marched against Dublin again in September to punish its Danish king, Haskulf, for having shown signs of resistance. Dublin surrendered in September. When Haskulf’s forces regrouped on the Isle of Man and returned with a fleet, Strongbow dispersed the Danish force, apparently with little effort.

Diarmuid Mac Murchada died in May 1171, unmourned by either the nobility or commoners of Leinster. Although Irish law clearly stated that a successor was to be chosen by the people, that system did not please the Normans, who had succeeded in installing Europe’s only completely feudal system in England after 1066. Strongbow, having married Aoife Ní Diarmuid, announced that he was the new ruler in her right and proclaimed himself Earl of Leinster.

Brutal as the initial Norman conquest of Ireland was, it still cannot be compared with the later subjugation of the island, particularly during and after Elizabethan times. While the Normans were cruel and unprincipled, their invasions ultimately resulted in a simple change of rulers, with no basic change in the culture or civilization. In Italy, the Normans became Italian; in Sicily, Sicilian; and in France, they became merely one more breed of Frenchmen. Nowhere was their assimilative tendency more evident than in Ireland, where the invaders adopted the Irish language, culture and customs to such an extent that they became, in the famous phrase, Hibernicis ipsis Hibernior–‘More Irish than the Irish.’ That assimilation was so prevalent among the new rulers that an actual distinction would be made in law (particularly in the infamous and oppressive Statutes of Kilkenny) between ‘native Englishmen’ and ‘Englishmen born in Ireland’ (i.e., resident Normans).

Although Strongbow had declared himself the new ruler of Leinster, he had yet to convince either the Irish chiefs and princes or Henry II. At reports of de Clare’s successes in Ireland, the English king had grown suspicious and jealous. Afraid that de Clare would establish himself as an independent monarch, the king demanded that Strongbow and all the rest of his subjects return to England forthwith. Nothing could have better suited the Irish, but it was not to be.

Having had prior experience of Henry’s wrath, Strongbow quickly found reasons to avoid going to England–some of those reasons were forced upon him by the Irish. Haskulf and Godred, the Danish king of the Isle of Man, landed near Dublin in mid-May 1171, only to be caught between the Norman forces of brothers Miles and Richard de Cogan, and destroyed. Arriving too late to save his ally Haskulf, the ard righ and his princes lay siege to Dublin until September, when Strongbow suddenly sallied out, surprised the Irish camp at Castleknock and scattered Ruairí’s army, capturing a large amount of booty and provisions. He immediately invaded and devastated Meath and Breffni, then quickly turned to the south to relieve his half brother, Robert FitzStephen, who was under siege in Wexford.

Strongbow arrived too late to save the city, however, and hard upon the heels of that disappointment he received a second summons to present himself before Henry in London without further delay. De Clare may have been reluctant to go to England, but he was far from stupid, especially with a royal ‘or else’ hanging over his head.

He left immediately and appeased his royal master’s wrath by laying his gains at the king’s feet, asking only to retain Leinster. His cupidity excited by Strongbow’s report, Henry decided that the situation in Ireland demanded his personal attention. The king landed in Waterford in October 1171, accompanied by a force of 500 knights and 4,000 men at arms.

Awed by such a display of force, a large number of Irish princes and chiefs in the south and east paid Henry homage–and thus planted the seeds of future misunderstanding and strife. The Irish viewed their offering of homage to this foreign king as a tribute to his power and strength–not something that affected their sovereignty or independence. The Normans, coming from the almost perfect feudal society they had installed in England, looked on this homage as acknowledgement by the Irish chiefs of the English king as their liege lord. Thus the Irish could view a fight against the Norman invader as a struggle between two independent sovereignties, while the Normans would naturally view it as treason.

Despite Henry’s success in the south and east, none of the Irish chiefs and princes of the west or north made submission–nor did the ard righ, although Ruairí was increasingly alarmed at the large number of defections to the enemy camp. Finally, Ruairí sent an envoy to Henry, inviting him to a parley at the river Shannon. Henry did not accept the invitation in person but sent his own envoys, through whom the ard righ made a pact of peace and friendship with Henry.

Henry kept busy that winter holding court in Dublin in a temporary ‘field palace’ built of woven willow branches. His lavish hospitality helped win the fealty of the various Irish princes who had submitted to him and contrasted sharply with the more familiar brutality and barbarism of the Norman invaders. Henry put a stop to further acquisition of land by the rapacious Normans, and such was his political skill that he managed to put himself in the position of being the one true protector of the Irish against the rapacity of the noble adventurers who saw Ireland as the perfect opportunity to grow wealthy and powerful.

In large measure, the kings of England managed to maintain that good impression for centuries; even Henry’s son, John, while seen as the worst of kings by the English, was called ‘Good King John’ by the Irish. Ireland’s first viceroy, Henry’s own seneschal, FitzAldelm de Burgo (progenitor of the Burke family), was under orders to refuse permission to extend the conquest, which made him extremely unpopular with the Normans, although they largely ignored English authority anyway.

When Henry returned to England at Easter, trouble resumed. Relieved of the watchful eye of the king, the Normans restarted their aborted campaigns. Almost immediately the Irish began to rise up against the Normans, who–now that their methods and arms were no longer unfamiliar–seemed less formidable. Pitting native strategy against Norman skill, the Irish inflicted several defeats on the once-invincible invaders. Even Strongbow was bottled up in Waterford and in danger of being captured. Only timely aid from Wales saved the new Earl of Leinster from losing his liberty and possessions–and quite probably his life as well.

Even Ard Righ Ruairí fielded a large force that overran Meath and might easily have captured Dublin and driven the foreigners out of Ireland completely but for his indecision. Instead, he thought it to his advantage to make a treaty with Henry acknowledging him as overlord but confirming Ruairí in the high kingship of five-sixths of Ireland.

This ‘Treaty of Windsor’ would be virtually ignored by both the Irish and the Normans, however. With foreigners occupying and controlling a substantial portion of the country, the confusing issue of who ruled what, and the authority of the ard righ effectively abolished by his own actions, the country dissolved into almost complete anarchy. The Irish continued to fight among themselves, and the Normans began to have falling-outs as well. It was not uncommon, as had happened with the earlier Viking invasions, for both Irish and Norman to unite with each other against either Norman or Irish adversaries.

With the destruction of the native system of government and the failure of the Irish to form a united front to drive out the invaders, the victory of the Normans in Ireland was assured. Although absolute control of the country would not be established for centuries–due to the tenacity of the Irish in refusing to admit defeat–for all intents and purposes Ireland would now be seen as an English possession.


This article was written by Michael D. Greaney and originally appeared in the December 1998 issue of Military History magazine.

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