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View Tree for King Dermot MacmurroughKing Dermot Macmurrough (b. 1110, d. 01 May 1171)

King Dermot Macmurrough (son of King Donnchad Macmurrough and Orlaith Ingen O Braenain)80 was born 1110 in Leinster, Ireland80, and died 01 May 1171 in Ferns, Leinster, Ireland80. He married More O Toole, daughter of Murcertac O Toole and Inghin O Byrne.

 Includes NotesNotes for King Dermot Macmurrough:
Diarmait Mac Murchada (also known as Diarmait na nGall, "Dermot of the Foreigners"), anglicized as Dermot MacMurrough (died 1 January 1171) was the King of Leinster, and is often considered to have been the most notorious traitor in Irish history. Ousted as King of Leinster, he invited King Henry II of England to assist him in regaining the throne. The subsequent invasion led to Henry becoming Lord of Ireland himself, and marked the beginning of eight centuries of English dominance.

Early Life and Family
Mac Murchada was born in 1110, a son of Donnchad, King of Leinster and Dublin; he was a descendant of Brian Boru. His father was killed in battle in 1115.

Mac Murchada had many wives and concubines, the first of whom, Mór Ua Tuathaill, was mother of Aoife of Leinster and Conchobar Mac Murchada. By Sadb of Uí Faeláin, he had a daughter named Orlaith who married Domnall Mór, King of Munster. He had two illegitimate sons, Domnall Cáemánach (died 1175) and Énna Cennselach (blinded 1169).

King of Leinster
After the death of his older brother, Mac Murchada unexpectedly became King of Leinster. This was opposed by the then High King of Ireland, Tairrdelbach mac Ruaidri Ua Conchobair who feared rightly so that Mac Murchada would become a rival. King Tairrdelbach sent one of his allied Kings, the belligerent Tigernán Ua Ruairc to conquer Leinster and oust the young Mac Murchada. Ua Ruairc went on a brutal campaign slaughtering the livestock of Leinster and thereby trying to starve the province's residents. Mac Murchada was ousted from his throne, but was able to regain it with the help of Leinster clans in 1133. Afterwards followed two decades of an uneasy peace between Ua Conchobair and Diarmait. In 1152 he even assisted the High King raid the land of Tigernán Ua Ruairc who had by then become a renegade. Mac Murchada also abducted Ua Ruairc's wife Derbforgaill along with all her furniture and goods, with the aid of Derbforgaill's brother, a future pretender to the kingship of Meath.

After the death of the famous High King Brian Boru in 1014, Ireland was at almost constant civil war for two centuries. After the fall of the O'Brien family (Brian Boru's descendants) from the Irish throne, the various families which ruled Ireland's four provinces were constantly fighting with one another for control of all of Ireland. At that time Ireland was like a federal kingdom, with four provinces (Ulster, Leinster, Munster and Connaught) each ruled by kings who were all supposed to be loyal to the High King of Ireland.

Exile, Return and Death
In 1166, Ireland's new High King and Mac Murchada's only ally Muirchertach Ua Lochlainn had fallen, and a large coalition led by Tigernán Ua Ruairc (now Mac Murchada's arch enemy) marched on Leinster. Ua Ruairc and his allies took Leinster with ease, and Mac Murchada and his wife barely escaped with their lives. Mac Murchada escaped to England where he formed an alliance with King Henry II who helped him organize a mercenary army of Norman and Welsh soldiers to invade Ireland. Among them were Richard de Clare, 2nd Earl of Pembroke, alias Strongbow, who married Mac Murchada's daughter, Aoife of Leinster, in 1170.

In his absence Ruaidri mac Tairrdelbach Ua Conchobair (son of Mac Murchada's former enemy, High King Tairrdelbach) had become the new High King of Ireland. Mac Murchada planned not only to retake Leinster, but to oust the Uí Conchobair clan and become the High King of Ireland himself. He quickly retook Dublin, Ossory and the former Viking settlement of Waterford, and within a short time had all of Leinster in his control again.

He then marched on Tara (then Ireland's capital city) to oust Ruaidri. Mac Murchada gambled that Ruaidri would not hurt the Leinster hostages which he had (including Mac Murchada's eldest son, Conchobar Mac Murchada). However Ua Ruairc forced his hand and they were all killed.

Diarmait's army lost the battle and the Norman and Welsh mercenaries whom he had hired soon aided an invasion by England's Henry II in 1169. Mac Murchada lost his will to fight after his son's death, retreated to Ferns and died a few months later.

Although in modern Irish history Diarmait Mac Murchada is often seen as a traitor, his intention was not to aid an English invasion of Ireland, but rather to use Henry's assistance to become the High King of Ireland himself. He had no way of knowing Henry II's ambitions on Ireland.

Gerald of Wales, a Cambro-Norman historian who visited Ireland and whose uncles and cousins were prominent soldiers in the army of Strongbow, said of Mac Murchada:

"Now Dermot was a man tall of stature and stout of frame; a soldier whose heart was in the fray, and held valiant among his own nation. From often shouting his battle-cry his voice had become hoarse. A man who liked better to be feared by all than loved by any. One who would oppress his greater vassals, while he raised to high station men of lowly birth. A tyrant to his own subjects, he was hated by strangers; his hand was against every man, and every man's hand against him."
Death and Descendants
After the invasion the Normans conquered Ireland by playing one Irish family off against another. Ua Conchobair was soon ousted, first as High King and eventually as King of Connaught. Attempting to regain his provincial kingdom, he turned to the English as Mac Murchada had before him. By 1171, England directly controlled a small territory in Ireland surrounding the city of Dublin known as "the Pale", while the rest of Ireland was divided between Norman and Welsh barons sent by the English, and the various Irish Clans (like the Uí Conchobair who retained Connaught and the Uí Néill who retained Ulster).

Subsequently most of the ruling Norman families began to intermarry with the Irish. Eventually they allied with Irish clans against England, adopted the Irish language and as the English put it "became more Irish than the Irish themselves" prompting a second English invasion centuries later.

It has also been claimed that US President George W.Bush is a descendent of Dermot McMurrough, as well as the Norman warlord Strongbow who led the English invasion of Ireland.,12271,1399353,00.html

See also Kings of Leinster

Annals of the Four Masters, ed. J. O'Donovan; 1990 edition.
Expungntio Hibernica, by Geraldus Cambrensis. Martin & Moody, editors.
Irish Kings and High Kings, Francis J. Byrne, 1973.
The Norman Invasion of Ireland, by Richard Roache, 1998.
War, Politics and the Irish of Leinster 1156-160, Emmett O'Byrne, 2004.
Gerald of Wales
Source for Genealogy
Uí Cheinnselaig Kings of Laigin, "Irish Kings and High Kings" by Francis J. Byrne, page 290, Dublin, 1973.
The MacMurrough-Kavanagh kings of Leinster, "War, Politics and the Irish of Leinster", Emmett O'Byrne, Dublin, 2004, Outline Genealogies I, Ia, Ib,, pages 247-249.
Retrieved from ""
Categories: 1171 deaths | History of Ireland | Medieval Gaels

At least he was Gael-Edward Bruce
In the middle of the 12th Century Ireland was caught in a time of weakness, as there was no current High King. The chieftains were fighting among themselves for power and one in particular, Diarmuid (Dermot) MacMurrough (d. May 1, 1171), had hopes of the High Kingship of Ireland himself.

Dermot MacMurrough was the Irish King of Leinster who succeeded his father Enna's throne in 1126. MacMurrough faced many rivals for the throne and he settled his problems by killing or blinding the 17 Chieftans in Northern Leinster who disputed his kingship. In 1153 MacMurrough abducted the wife of Tiernan O'Ruark, king of Breifne (what we know today as the modern counties of Leitrim and Cavan). Within a year, MacMurrough was attacked and the stolen wife returned but his powerful northern allies prevented the punishment he so deserved.

After thirteen years of bitter feuding, MacMurrough was expelled from his kingdom by Roderic (Rory O'Connor), high king of Ireland. MacMurrough fled to England and immediately went to King Henry II who granted permission for the exiled ruler to enlist the aid of several Anglo-Norman lords, in particular Richard de Clare (b. c. 1130 d. April 20, 1176, Dublin, Ire.) who is also known by the name Strongbow.

Little did Dermot MacMurrough realize that by enlisting the help of the Anglo-Normans to settle an internal dispute he would lead the English right into the conquest of Ireland itself.

Initially, the Anglo-Norman invasion of Ireland was viewed in terms of assistance to an exiled ruler. But MacMurough's continued requests for help and his own greed brought more and more foreign troops to Ireland. Upon MacMurrough's death in May, 1171, Strongbow took charge of all the conquered lands and laid these at the feet of the English King, Henry II.

Strongbow's easy victories emboldened Henry to lead his own invasion of Ireland in October 1171. English superiority was readily apparent and Ireland's Princes and Kings quickly swore fealty to their new ruler.

Although the Gaels were scattered and without leadership they never really capitulated. And even though the invaders quickly dotted the landscape with castle after castle, in 1258 the greatest Irish Clans remaining elected Brian O'Neill as their High King in an attempt to unite the country. But the Irish forces were weak compared to the Anglo-Normans and were quickly defeated in the disastrous Battle of Downpatrick in 1260. The Irish fought in fine linen and fell like wheat in front of the invaders who fought in a mass of iron and in organized groups on horseback. Their new High King was killed and their hopes, while not dashed, waned considerably.

In 1263, the Irish tried again and the offer of High Kingship went to King Haakon IV (b. 1204) of Norway. King Haakon brought the gall-oglach into the fray. The gall-oglach (gallowglass) were a combination of Scot and Viking who lived on the western islands of Scotland under Norse control. They were huge men for the time, heavily armed, mail armored, battle-axe-swinging harvesters of death.

Sensing an opportunity, the Scotts took advantage of the Gallowglass' absence and recovered the territory in the islands. King Haakon tried, but failed to recoup his loss and later died of his injuries in the Orkney Islands in December 1263 before he could formally accept the Irish Crown. Now without a home, the gallowglass stayed in Ireland and began turning the tide in favor of the Irish.

Although the small numbers of gallowglass prevented a swift Irish victory, Anglo-Norman power faded in Ireland. Over the span of the next fifty years, more and more of the country fell back into the hands of the Gaels. Impatient, Donal O'Neill and the other Lords invited Edward Bruce to Ireland in 1315.

Edward was the brother of Robert the Bruce, King of Scotland. Together they had successfully defeated the English at the Battle of Bannockburn in 1314 and attained Independence for Scotland. In 1315 Edward was the Earl of Carrick, in Galloway, Scotland, and had thousands of unemployed soldiers in his domain. His ambitions needed an outlet, and another fight against the English seemed like the thing to do. Edward accepted, and on May 25th 1315 landed at Larne Harbor with the largest force to ever hit the island. Six thousand battle-hardened veterans clad in mail offloaded from the ships. Large numbers of light Irish infantry soon joined them and the Battles began in earnest.

The Gael alliance was almost unstoppable and started to reel off a string of victories. For this, Edward was well received and after almost a year he was crowned King of Erin (Ireland) at Dundalk on May Day, 1316. He soon had almost all of Northern Ireland in his grasp, and in September his brother Robert arrived to help him. They took most of the midlands of the Island but failed in taking Dublin, as they had no siege engines. Meanwhile, the beginning of a general famine was making it difficult to provide for his soldiers in the field. After going back to Ulster early in the year of 1317, Robert the Bruce returned to Scotland and the management of his kingdom with a promise of supplies and more men.

Little happened the next year, as the general famine prevented much fighting by the participants. Of notable exception was a battle at Disert O'Dea near Ennis, where the O'Brien's recovered their Kingship. But this was soon to change, as Edward Bruce had lost momentum and an army led by John de Birmingham was marching against him in the late summer of 1318.

Birmingham's forces were vastly superior to those of Edward Bruce, but he was emboldened by his string of victories and sallied forth against the menace. His force of Scots, Irish and Meath rebels met the army on October 14th, 1318 and were soundly defeated. Edward himself was slain after a gallant stand, his remaining Scots returning home however they could. Edward's allies were left leaderless and suffered greatly after this defeat. Thus, the English Lordship of Ireland was restored.

Whether or not a Scottish feudal monarchy in Ireland instead of an English one would have bettered things is not known. But the rampant pillaging of Middle Ireland by Bruce's Army most certainly caused a severe famine for over three years.

History is written by the victors, they say, so it is likely that Edward probably would have been judged differently had he been victorious in Ireland. Historian Edmund Curtiss, in his book, A History of Ireland, mentions Bruce being described as a "destroyer of Ireland in general, both of English and of Gael". … Well, as far as this writer is concerned, at least Edward was Gael.

More About King Dermot Macmurrough:
Date born 2: 1110, Leinster, England.80
Died 2: 01 Jan 1171, Ferns, Leinster, England.80

Children of King Dermot Macmurrough and More O Toole are:
  1. +Urlachen Of Leinster MacMurrough, b. 1142, Leinster, Ireland80, 80, d. date unknown, Y80, 80.
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