Alice — Maurice FitzGerald, Lord of Lanstephan. Maurice (son of Gerald de Windsor and Nest ferch Rhys, ap Tewdwr) was born Abt 1105; died Sep 1177. [Group Sheet]

1. Gerald FitzMaurice, 1st Lord of Offaly was born Abt 1150; died 15 Jan 1203/04, Wales.

Notes:

Arnulf of Montgomery (c. 1068-1118/1122) was an Anglo-Norman aristocrat, who played a role in the history of England, Wales, and Ireland.

Lineage

He was the youngest son of Roger de Montgomerie, 1st Earl of Shrewsbury and Mabel de Bellême.

Early career

Around 1093 he was part of the invasion of South Wales following the death in battle of Rhys ap Tewdwr. the last king of South Wales. Arnulf built a castle at Pembroke in West Wales, described by Giraldus Cambrensis as a "slender fortress of turf and stakes" under the command of one of his young officers, Gerald FitzWalter (aka Gerald de Windsor), who held it for Arnulf in the face of the great Welsh uprising of 1093. In 1094 king William II of England rewarded Arnulf with the formal lordship of Pembroke; some historians say that he was in fact created Earl of Pembroke. In any case the lordship was smaller than the later Pembrokeshire.

Arnulf's holdings were greatly expanded in 1096 when Rufus gave him the lordship of Holderness, which in addition to that part of Yorkshire included land in Lincolnshire.

Rebellion & Banishment

It is likely that Arnulf had been designated heir of his brother Hugh of Montgomery, 2nd Earl of Shrewsbury, but after Hugh's death in 1098 Arnulf was outmaneouvered by their eldest brother, Robert of Belleme, 3rd earl of Shrewsbury. This caused some rift between the brothers; nevertheless Arnulf participated in their 1101 rebellion against Henry I of England. As a result, they lost their English and Welsh lands, and were exiled from England.

Ireland

Arnulf turned his attention to Ireland, where, prior to the Montgomery rebellion, he had sent Gerald de Windsor to secure for him the hand in marriage of Lafracoth, daughter of the Irish king Muircheartach Ua Briain; by 1102, Arnulf was mentioned by Muirchertach as his son-in-law in a letter to the Archbishop of Canterbury Anselm of Bec. Muirchertach provided support for the Montgomerys' rebellion; as a result King Henry I of England placed a trade embargo on Ireland.

Orderic Vitalis states that Arnulf went to Ireland after the rebellion failed and served for Muirchertach Ua Briain, although the Irish Annals make no mention of this. He further relates that Arnulf was used by Muirchertach to defeat Magnus Barelegs. Then, "when the Irish had tasted blood by killing King Magnus and his companions they grew more unruly and suddently turned to kill the Normans. Their king took his daughter away from Arnulf and gave the wanton girl in unlawful marriage to one of his cousins. He resolved to murder Arnulf himself as a reward for his alliance, but the latter, learning of the execrable plots of this barbarous race, fled to his own people and lived for twenty years afterwards with no fixed abode."

Later life

In later years Arnulf was in the entourage of count Fulk V of Anjou.

A tombstone in Tulsk, Ireland bears the name Arnoulf and the date 1122.

Arnulf died sometime between 1118 and 1122. Some sources list him as having died without issue[1], although other sources list him as having left two daughters.

Arnulf married Lafracota Bef 1103. [Group Sheet]

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Notes:

Roger de Montgomery, Earl of Shrewsbury was the son of Roger de Montgomery, Seigneur de Montgomery. He married Mabel de Bellême, daughter of William Talvas, Signeur d'Alençon, between 1050 and 1054.

He was styled as Earl of Chichester. He was created 1st Earl of Arundel [England] in December 1067, receiving grants including one third of the county of Sussex, including the city of Chichester and the Castle of Arundel. He was created Earl of Shrewsbury [feudal barony] in 1070, receiving grants of nearly the whole of Shropshire.

Roger de Montgomerie (died 1094), also known as Roger the Great de Montgomery, was the first Earl of Shrewsbury. His father was also Roger de Montgomerie, and was a relative, probably a grandnephew, of the Duchess Gunnor, wife of Duke Richard I of Normandy. The elder Roger had large holdings in central Normandy, chiefly in the valley of the Dives, which the younger Roger inherited.

Life

Roger was one of William the Conqueror's principal counsellors. He did not fight in the initial invasion of England in 1066, instead staying behind to help govern Normandy. According to Wace’s Roman de Rou, however, he commanded the Norman right flank at Hastings, returning to Normandy with King William in 1067. Afterwards he was entrusted with land in two places critical for the defense of England, receiving the rape of Arundel at the end of 1067 (or in early 1068), and in November 1071 he was created Earl of Shrewsbury; a few historians believe that while he received the Shropshire territories in 1071 he was not created Earl until a few years later.

Roger was thus one of the half dozen greatest magnates in England during William the Conqueror's reign. William gave Earl Roger nearly all of what is now the county of West Sussex, which at the time of the Domesday Survey was the Rape of Arundel. The Rape of Arundel was eventually split into two rapes, one continuing with the name Rape of Arundel and the other became the Rape of Chichester. Besides the 83 manors, in Sussex, his possessions also included seven-eighths of Shropshire which was associated with the earldom of Shrewsbury, he had estates in Surrey (4 manors), Hampshire (9 manors), Wiltshire (3 manors), Middlesex (8 manors), Gloucestershire (1 manor), Worcestershire (2 manors), Cambridgeshire (8 manors), Warwickshire (11 manors) and Staffordshire (30 manors). The income from Roger’s estates would amount to about £2000 per year, in 1086 the landed wealth for England was around £72,000, so it would have represented almost 3% of the nation’s GDP.

After William I's death in 1087, Roger joined with other rebels to overthrow the newly crowned King William II in the Rebellion of 1088. However, William was able to convince Roger to abandon the rebellion and side with him. This worked out favourably for Roger, as the rebels were beaten and lost their land holdings in England.

Roger first married Mabel de Bellême, who was heiress to a large territory on both sides of the border between Normandy and Maine. The medieval chronicler Orderic Vitalis paints a picture of Mabel of Bellême being a scheming and cruel woman. She was murdered by Hugh Bunel and his brothers, who in December 1077 rode into her castle of Bures-sur-Dive and cut off her head as she lay in bed. Their motive for the murder being that Mabel had deprived them of their paternal inheritance. Roger and Mabel had 10 children:

Robert de Bellême, Count of Alençcon in 1082, he succeeded his younger brother Hugh as 3rd Earl of Shrewsbury. He married Agnes, Countess of Ponthieu and died in 1131.
Hugh of Montgomery, 2nd Earl of Shrewsbury, died without issue 1098.
Roger the Poitevin,Vicomte d'Hiemois, married Adelmode de la Marche.
Philip of Montgomery.
Arnulf of Montgomery, married Lafracota daughter of Muirchertach Ua Briain.
Sibyl of Montgomory, she married Robert Fitzhamon, Lord of Creully.
Emma, abbess of Almenchêches.
Matilda (Maud) of Montgomery, she married Robert, Count of Mortain and died c. 1085.
Mabel of Montgomery, she married Hugh de Châteauneuf.
Roger of Montgomery, died young.

Roger then married Adelaide de Le Puiset, by whom he had one son, Everard, who entered the Church.

After his death, Roger's estates were divided. The eldest surviving son, Robert, received the bulk of the Norman estates (as well as his mother's estates); the next son, Hugh, received the bulk of the English estates and the Earldom of Shrewsbury. After Hugh's death the elder son Robert inherited the earldom.

Roger married Mabel de Bellême Between 1050 and 1054. Mabel (daughter of William, I Talvas and Hildeburg) died 02 Dec 1079; was buried 05 Dec 1079, Troarn, Calvados, Basse-Normandie, France. [Group Sheet]

Notes:

Mabel de Bellême (a.k.a. Mabel Talvas) (d. 1079), Dame de Alençon, de Séez, and Bellême, Countess of Shrewsbury and Lady of Arnudel. She was a member of the House of Bellême.

Life

Mabel was the daughter of William I Talvas and his first wife Hildeburg. She was the heiress of her father’s estates, her half-brother Oliver apparently being excluded. She also inherited the remainder of the Belleme honor in 1070 at the death of her uncle Yves, Bishop of Séez and Lord of Bellême. When their father was exiled by her brother Arnulf in 1048 she accompanied him until both were taken in by the Montgomery family. Between 1050-1054 she married Roger II de Montgomery, later 1st Earl of Shrewsbury. Roger II de Montgomery was already a favorite of Duke William and by being given the marriage to Mabel it increased his fortunes even further.

Her husband Roger had not participated in the Norman conquest of England but had remained behind in Normandy as co-regent along with Queen Matilda. He had also contributed 60 ships to Duke William's invasion force. He joined the king in England in 1067 and was rewarded with the earldom of Shropshire and a number of estates to the point that he was one of the largest landholders in the Domesday Book.

She and her husband Roger transferred the church of Saint-Martin of Séez to Evroul and petitioned her uncle, Yves, Bishop of Séez to build a monastery there on lands from her estates. The consecration was in 1061 at which time Mabel made additional gifts.

Her character

Of all of Orderic’s female subjects Mabel was the most cunning and treacherous; if not entirely for her own misdeeds then as the mother of Robert de Bellême, who had a reputation for savagery as well as cruelty. In one passage Orderic describes her as "small, very talkative, ready enough to do evil, shrewd and jocular, extremely cruel and daring."

In perpetuating her family’s feud with the Giroie family she set her sights on Arnold de Echauffour, she son of William fitz Giroie who her father had mutilated at his wedding celebration. She obtained part of his estates when she and her husband Roger convinced Duke William to confiscate his lands. In 1063 however, Arnold was promised forgiveness by the Duke and was to have his lands restored. To prevent this Mabel plotted to kill Arnold. She attempted to poison Arnold of Echauffour by placing it in a glass of wine but he declined to drink. Her husband's brother, refreshing himself after a long ride, drank the wine and died shortly thereafter. In the end though she bribed Arnold's chamberlain providing him with the necessary poison, this time being successful.

Excepting Theodoric, abbot of the abbey of Saint-Evroul, who she listened to at times, Mabel was hostile to most members of the clergy; but her husband loved the monks at Saint-Evroul so she found it necessary to be more subtle. In an incident in 1064, she deliberately burdened their limited resources by visiting the abbey for extended stays with a large retinue of her soldiers. When rebuked by Theodoric the abbot for her callousness she snapped back that the next time she would visit with an even larger group. The abbot predicted that if she did not repent of her evilness she would suffer great pains and that very evening she did. She left the abbey in great haste as well as in great pain and did not abuse their hospitality again.

Mabel continued her wickedness causing many nobles to lose their lands and become destitute. In 1077 she took the hereditary lands of Hugh Bunel by force. Two years later while resting after a bath, she was murdered in her bed by the same Hugh Bunel Hugh had enlisted the help of his three brothers, gained entry to the castle of Bures on the Dive and struck off her head with his sword. The murderers were pursued but escaped by destroying a bridge behind them. Mabel's murder occurred on 2 December 1079 and she was buried three days later at Troarn.

Epitaph

Her epitaph is notable as an example of monks bowing more to “the partiality of her friends than to her own merits":

Sprung from the noble and the brave,
Here Mabel finds a narrow grave.
But, above all woman’s glory,
Fills a page in famous story.
Commanding, eloquent, and wise,
And prompt to daring enterprise;
Though slight her form, her soul was great,
And, proudly swelling in her state,
Rich dress, and pomp, and retinue,
Lent it their grace and houours due.
The border’s guard, the country’s shield,
Both love and fear her might revealed,
Till Hugh, revengeful, gained her bower,
In dark December’s midnight hour.
Then saw the Dive’s o’erflowing stream
The ruthless murderer’s poignard gleam.
Now friends, some moments kindly spare,
For her soul’s rest to breathe a prayer!

Family

Mabel and her husband, Roger de Montgomery had ten children:

Roger of Montgomery, oldest son, died young.
Robert de Bellême, Count of Alençcon in 1082, he succeeded his younger brother Hugh as 3rd Earl of Shrewsbury. He married Agnes, Countess of Ponthieu and died in 1131.
Hugh of Montgomery, 2nd Earl of Shrewsbury, died without issue 1098.
Roger the Poitevin,Vicomte d'Hiemois, married Adelmode de la Marche.
Philip of Montgomery.
Arnulf of Montgomery, married Lafracota daughter of Muirchertach Ua Briain.
Sibyl of Montgomory, she married Robert Fitzhamon, Lord of Creully.
Emma, abbess of Almenchêches.
Matilda (Maud) of Montgomery, she married Robert, Count of Mortain and died c. 1085.
Mabel of Montgomery, she married Hugh de Châteauneuf.

Notes:

Muircheartach Ua Briain (old spelling: Muirchertach Ua Briain) (c. 1050 - c. 10 March 1119), son of Toirdelbach Ua Briain and great-grandson of Brian Bóruma, was King of Munster and later self declared High King of Ireland.

Background

Muirchertach Ó Briain was a son of Toirdelbach Ua Briain, a previous Dalcassian king of Ireland. In 1086 his father died and the province of Munster from which he had claimed kingship of Ireland had been split between his three sons: Tadc, Muirchertach and Diarmait. Tadc died soon after, and Muirchertach banished Diarmait from Munster, claiming its kingship for himself.

King of Munster

Between 1086 and 1101, Muirchertach consolidated and strengthened his position as province-king of Munster. He went on forays into Mide and Leinster in 1089 and took the kingship of Leinster and fought for the Viking town of Dublin. In 1093, he accepted the submission of Domnall mac Flainn Ua Maíl Shechnaill, the Uí Néill king of Tara, and also made peace with his brother Diarmait at Cashel.

King of Ireland with opposition

In 1094, Muirchertach fought the kings of Leth Cuinn and Gofraid, king of Dublin. He went with his army to Dublin and banished Gofraid, and brought about the killing of Domnall Ua Maíl Shechnaill. He asserted supremacy over the Uí Néill kingdom of Mide.

In 1101 he declared himself High King and travelled the island provinces. It was in this year that he gave the fortress at on the rock of Cashel as a gift to the Church.

Alliance with Arnulf de Montgomery

In an effort to gain military support against Henry I, Arnulf de Montgomery sent his steward, Gerald of Windsor, to Ireland to negotiate terms with Muirchertach. According to a Welsh chronicle (Sean Duffy, p. 45, 1997), Arnulf "though to make peace with the Irish and to obtain help from them. And he sent messengers to Ireland, that is Gerald the Steward (Gerald of Winsor) and many others, to ask for the daughter of King Murtart for his wife. And that he easily obtained; and the messengers came joyfully to their land. And Murtart sent his daughter and many armed ships along with her to his aid. And when the earls had exalted themselves with pride because of those events, they refused to accept any peace from the king."

De Montgomery and his brother Robert, were however defeated by Henry and fled to Ireland. The Montgomery brothers fought under Muirchertach during his campaign with Magnus Barelegs, but when de Montgomery attempted to seize the kingship for himself, Muirchertach "took his daughter away from Arnulf and gave the wanton girl in an unlawful marriage to one of his cousins. He resolved to kill Arnulf himself as a reward for his alliance, but the latter ... fled to his own people and lived for twenty years afterwards with no fixed abode." (Sean Duffy, 1997, p. 46). Despite their checkered relationship, some sources list Lafracoth, the daughter of Muirchertach, as the mother of two daughters by Arnulf, Alice de Montgomery and Marie de Montgomery.

Magnus Barelegs

In 1102, Muirchertach cemented an alliance with Magnus Barefoot, king of Norway by marrying his daughter Blathmin Ua Briain to Magnus's son, Sigurd I Magnusson. Muirchertach now took part in a campaign with Magnus to assert control over Ulster, successfully defeating opposing Irish forces. After a year of campaigning, as his army was readying to depart back to Norway, King Magnus was ambushed and killed by an Irish army in Ulster. With Magnus's death, Muirchertach's daughters marriage was disavowed by the Norwegians, weakening Muirchertachs proclaimed position as High King.

In 1114 the king became sick to the point where "he became a living skeleton". In response to the king's misfortune, his brother Diarmait took control of the kingship of Munster and banished Muirchertach. The following year Muirchertach regained his strength and undertook a campaign to regain control of Munster and successfully captured Diarmait. Only later did the king regain control of Munster.

Final years

In 1119, Muirchertach Ua Briain died.

Assessments

Anthony Condon (1979, p. 398) remarked of Ó Briain:

"Muirchertach Ó Briain was an ambitious, modernizing and outward-looking king whose goal was to make himself king of Ireland as much as William Rufus and Henry I were kings of England; in reality his position was, perhaps, more analogous to that of Philip I in France ... but his actualy [sic] authority in Ireland, especially at the height of his power in the first years of the twelfth century, greatly exceeded that of Phillip in France. ... Ua Briain ... pursued a vigorous foreign policy which was to carry his activities beyond his own shores."

In the latter regard, Condon (1979, p. 415) views "Ua Briain's activities in the Irish Sea area [as] a mixture of old and new, of pragmstisim and idealism ... But they are invested with a modern purpose. Ua Briain makes one marriage with the king of Norway, and another with one of the most powerful non-royal families in Europe; he treats with the king of Scotland; his aid to the Welsh princes acts as a stabilizing influence in Welsh politics; he incurs trade sanctions from the king of England, and negotiates their suspension. Altogether, Muirchertach Ó Briain lifted his head above the domestic power struggle and sought to involve Ireland in the international politics of Europe, so that some sixty years later, these activities were still well remembered, and are reflected in the vitae of St. Flannan of Killaloe."

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Roger — Josceline. [Group Sheet]

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Notes:

William Talvas, Signeur d'Alençon gained the title of Signeur d'Alençon [Normandy].

William I Talvas (c. 995 - 1052), seigneur of Alençon. According to Orderic Vitalis his nickname Talvas meaning shield, presumably alluded to his hardness or callousness like that of a shield. He was a member of the House of Bellême.

Life

He was a son of William of Bellême and Mathilde of Condé-sur-Noireau. He held lands at Bellême, Domfront and Alençon, He obtained the lands of Bellême from his brother Yves de Bellême, Bishop of Séez who held them of the King of France while Alençon was held of the Duke of Normandy and Domfront of the Count of Maine.

While as treacherous and self-serving as any of his family before him he surpassed them in wickedness and cruelty. He had married a Hildeburg, daughter of a nobleman named Arnulf, but he had his wife strangled on her way to church, according to Orderic, because she loved God and would not support his wickedness. William married secondly a daughter of Ralf de Beaumont, Viscount of Le Mans.

Among the private feuds going on during the minority of Duke William was one that erupted between William Talvas and William fitz Giroie. William fitz Giroie was a vassal of William Talvas and his father Giroie had assisted Talvas' father and uncle in the struggles against Herbert I Wake-dog, Count of Maine. William fitz Giroie himself had greatly assisted William Talvas in obtaining his own lands, apparently by force. But William fitz Giroie was also a vassal of Geoffrey de Mayenne, an adherent, in turn, of the Count of Maine. About 1044 William Talvas attacked the castle of Montaigu which was being defended by William fitz Giroie. Unable to defeat the castle William Talvas captured Geoffrey de Mayenne and held him prisoner until William Fitz Giroie destroyed the castle of Montaigu. William fitz Giroie immediately razed his own castle to free his lord and in return Geoffrey de Mayenne built fitz Giroie a new castle at St. Cenery on the river Sarthe. This apparently caused great resentment in William Talvas.

On the occasion of his second wedding, William Talvas invited William fitz Giroie to attend. Suspecting nothing fitz Giroie while a guest at the festivities was suddenly seized by Talvas' men and imprisoned, then according to Orderic horribly mutilated and blinded before being released. Somehow William Giroie survived his torture and mutilation and retired to Bec Abbey to live out the remainder of his life as a monk. To avenge this atrocity the sons and kinsmen of William fitz Giroie sacked and destroyed the lands of William Talvas who would not face them in the field. Finally, Talvas' son Arnulf rebelled and exiled his father, now reviled by everyone. He wandered until he was taken in by the de Montgomery family whose son Roger agreed to marry his daughter Mabel in return for the lands William lost. It seems certain that after the death of Arnulf the following year, that William Talvas recovered his lands. William confirmed a gift to St. Aubin of Angers made by his brother Yves circa 1060-2 and after that nothing more is heard of him.

Family

By Hildeburg, his first wife, William had two children:

Arnulf de Bellême, who deprived his father of his estates and wealth and was dead by 1049.
Mabel de Bellême, who married Roger de Montgomerie, 1st Earl of Shrewsbury and was murdered 2 Dec 1079

His second wife, a daughter of Ralf de Beaumont, may have been the mother of his son:

Oliver who after long service in the wars, became a monk at Bec.

William Talvas is said to have cursed the infant William, later to become William the Conqueror, in his cradle predicitng the child would be the downfall of the house of Bellême.

William — Hildeburg. [Group Sheet]

Notes:

Toirdhealbhach Ua Briain (old spelling: Toirdelbach Ua Briain), anglicised Turlough O'Brien (1009 - 14 July 1086), was King of Munster and effectively High King of Ireland. A grandson of Brian Bóruma, Toirdelbach was the son of Tadc mac Briain who was killed in 1023 by his half-brother Donnchad mac Briain.

For the first forty years of his life nothing is known of Toirdelbach. It was not until the 1050s that he found allies in Connacht and in Leinster, particularly the powerful King of Leinster Diarmait mac Maíl na mBó, who would aid his claims to be ruler of Munster. It took perhaps ten years of sustained attack to remove his uncle Donnchad from power, and send him into exile, and to place Toirdelbach in power in Munster as Diarmait's faithful ally.

On Diarmait's death Toirdelbach took over the reins of power, establishing himself as ruler of more than half of Ireland. While not a great military leader, he was a capable politician whose influence extended as far north as Ulaid and who made and unmade Kings of Connacht. He died after more than two decades in power, following a lengthy illness, still in control of events. His son Muirchertach Ua Briain would be the leading king of his day, and his grandson Toirdelbach Ua Conchobair would be greater yet.

Background

Brian Bóruma was the first man in many centuries to establish himself as High King of Ireland by force of arms. Previous men reckoned High King had belonged to the great Uí Néill kindred, the large group of families who claimed to descend from Niall of the Nine Hostages, which dominated much of central and northern Ireland from the 7th century onwards. No king from the south, where Brian's kindred, the hitherto rather obscure Dál gCais of the region of Tuadmumu (north Munster), had come close to dominating Ireland since the time of Feidlimid mac Crimthainn in the early 9th century, and none had been included in the more widely accepted lists of high kings in historic times. The last effective high king of Ireland from Munster was Cathal mac Finguine (d. 742), and likely before him the prehistoric Crimthann mac Fidaig.

Brian, building on his own resources and those of the Viking towns of the south such as Limerick and Cork, first took control of Munster, overthrowing the domination of the Eóganachta, a kindred which had dominated the kingship of Munster as effectively as the Uí Néill had dominated the High Kingship, and for just as long. With the Uí Néill disunited and the resources of Munster at his command, Brian first brought the Uí Néill High King Máel Sechnaill mac Domnaill to recognise him as an equal, and then to acknowledge him as the master of Ireland. Brian met his death at the Battle of Clontarf on 23 April 1014-Good Friday-fighting against the King of Leinster and his allies. In myth and medieval pseudohistory, as exemplified by the Cogadh Gaedhil re Gallaibh written in the time of Toirdelbach's son, this battle would become the last and greatest between the Irish and the Vikings, and Brian would become the greatest of all Irish kings.

Family quarrels

Toirdelbach was the son of Tadc mac Briain, son of Brian Bóruma, and Mór, daughter of Gilla Brigte Ua Maíl Muaid of Cenél Fiachach. His father was killed in 1023, probably on the orders of his half-brother Donnchad mac Briain who thereby made himself king of Munster. Donnchad, while he successfully retained control of Munster for four decades, was never able to achieve the same success as Brian. Epigraphic evidence shows that he aimed to be king of Ireland, and perhaps considered himself to be such, but the annalists and later historians recognised no such pretensions.

As for Toirdelbach, the annals record nothing of him until the 1050s, at which time he was seeking, and finding, outside assistance against his uncle. Donnchad's main rivals were Diarmait mac Maíl na mBó, King of Leinster from 1042, and Áed in Gaí Bernaig, King of Connacht from 1046. Diarmait in particular was a serious threat; allied with Niall mac Eochada, King of Ulster, he installed his son Murchad as ruler of Dublin in 1052, driving out Donnchad's brother-in-law and ally Echmarcach mac Ragnaill. From the beginning of the 1050s onwards, Donnchad came under sustained attack from both Áed and Diarmait. Toirdelbach first joined with Áed in the early 1050s, raiding into Tuadmumu in 1052 and inflicting a heavy defeat on Donnchad's son Murchad in Corco Mruad, the north-west of modern County Clare in 1055. By 1058 Toirdelbach had gained Diarmait's support, for he was present when Diarmait, the Leinstermen and the Osraige drove Donnchad from Limerick, which he burned so that it would not fall into the hands of his enemies, and defeated him at Sliabh gCrot in the Galtee Mountains.

In 1060 Donnchad attempted to divide his enemies by submitting to Áed. This was unsuccessful as Áed attacked again in 1061, razing the Dál gCais fortress at Kincora and burning their church at Killaloe. Injury was added to insult when Diarmait brought an army, and Toirdelbach in his train, to Munster in 1062. Donnchad's son Murchad led the unsuccessful resistance, and even when Diarmait returned to Leinster, Toirdelbach defeated his kinsmen. By 1063, Donnchad was beaten. Deposed, he went on pilgrimage to Rome where he died the following year. Diarmait installed Toirdelbach as a puppet king in Munster.

Diarmait mac Maíl na mBó

Following Donnchad's deposition, Toirdelbach was one of Diarmait's key allies, particularly in Diarmait's final years when his authority was challenged within Leinster. In 1066 Diarmait and Toirdelbach each paid 30 ounces of gold to the king of Ciarraige Luachra of West Munster for his help in assassinating their enemies. In 1067 they campaigned together to defeat and kill the king of Ciarraige Luachra. Toirdelbach's nephew Murchad son of Donnchad was killed in 1068 while raiding in the midlands.

The Annals of Innisfallen record to Toirdelbach as a law-maker, reporting that in 1068: "A law and ordinance was made by Tairdelbach Ua Briain-and no better law was enacted in Mumu for a long time-with the result that neither cow nor horse was housed [at night] but allowed to wander at will." In the same year, and perhaps related to this law-making, Máel Ísu mac Amalgada, comarba Pátraic or abbot of Armagh and successor of Saint Patrick, visited Munster for the first time and received "his full visitation, both in tribute and offerings".

Toirdelbach's ally and protector Diarmait mac Maíl na mBó faced increasing difficulties in his final years, difficulties which led Toirdelbach to intervene on Diarmait's behalf against his enemies in Leinster. Diarmait's sons Murchad and Glúniairn died in 1070, leaving the succession uncertain and disputed. Later in 1070 Toirdelbach took an army into Leinster, carrying off hostages, and receiving the submission of the king of Osraige. Toirdelbach had to return to Leinster again in 1071 open warfare broke out between Diarmait's grandson Domnall, Murchad's son, and his nephew Donnchad, son of Domnall Remair. The annal states that the hostages Toirdelbach took were handed over into the keeping of Diarmait mac Maíl na mBó. Toirdelbach was not idle on his own account in these years. He led an army on a raid into the midlands in 1071, and had his soldiers build wooden bridges across the Shannon, evidently for military purposes, at Áth Caille (perhaps modern O'Briensbridge) and Killaloe.

Diarmait visited Munster in 1071, distributing gifts. Diarmait had earlier given Toirdelbach treasures which included Brian Bóruma's sword, and "the standard of the king of the Saxons". This was among Diarmait's last recorded acts before his death in battle on 7 February 1072.

Toirdelbach was the chief beneficiary of Diarmait's death, the Annals of Innisfallen recording that:

Toirdelbach Ua Briain went to Osraige and Leinster, burned Uí Cheinnselaig and brought away much booty and cows, and took hostages from it as well as from Leinster. And the foreigners gave him the kingship of Dublin, and he made prisoner the sons of Domnall, son of Máel na mBó, in Dublin, and brought back the hostages of Osraige on that occasion.

Conchobar Ua Máel Shechnaill, king of Mide, was murdered the next year, and Toirdelbach took advantage of this to ravage the midlands, followed by an expedition to Connacht where he obtained hostages from both the Uí Conchobair and the Uí Ruairc. He divided Leinster between various rivals, a policy of divide and rule which would serve him well. In Dublin he installed one Gofraid mac Amlaíb meic Ragnaill, perhaps a kinsman of Echmarchach mac Ragnaill, as his client king.

A campaign in 1075 directed against the Uí Néill and their allies in the north turned out less well. Toirdelbach's son Muirchertach was defeated by the Airgíalla near Áth Fhirdia (modern Ardee, County Louth) with heavy loss. At more or less the same time Gofraid was banished from Dublin by Toirdelbach, seemingly replaced by Domnall son of Murchad son of Diarmait mac Maíl na mBó, who ruled for only a short time before he died, and was replaced by Toirdelbach's son Muirchertach. With Muirchertach securely installed in Dublin, and another son, Diarmait, ruling over Waterford, Toirdelbach was master of half of Ireland.

The wider world

While Toirdelbach's son Diarmait, ruler of Waterford, raided Wales in 1080, in general Toirdelbach is seen as less interested in matters outwith Ireland than his protector Diarmait mac Maíl na mBó, or his son Muirchertach.

It was during Gofraid's short reign over Dublin, on 6 May 1074, that Donatus, first archbishop of Dublin died. This led the archbishop of Canterbury, Lanfranc of Pavia, to take an interest in Irish matters. Lanfranc, basing himself, he said, on Bede's writings, had already assured Pope Alexander II that Dublin formed part of the province of Canterbury and that it was for him to consecrate the new bishop. He also wrote to the Irish kings concerned, being careful not to cause offense. His letter to Toirdelbach calls him "magnificent king of Ireland", a title which might seem the more impressive had Lanfranc not also addressed Gofraid of Dublin as "glorious king of Ireland".

The Annals of Innisfallen report that "five Jews came from over sea with gifts to Toirdelbach, and they were sent back again over sea". The meaning and significance of this event is unclear. Hudson remarks that "[i]f the delegation wanted [Toirdelbach]'s approval for settling in Ireland they were disappointed". Bracken suggests that if this was the intention of the delegation, the otherwise astute Toirdelbach missed a significant opportunity to strengthen his position.

Divide and rule

Toirdelbach employed the policy of divide and rule to maintain control of Leinster and to prevent the emergence of a rival in Connacht. In the north, he supported the Ulaid to weaken the Cenél nEógain kings of Ailech. This policy was successful in keeping Leinster pacified, but was less successful in dealing with the Cenél nEógain of the north and the kings of Connacht in the west.

The Cenél nEógain, who appear to have had no widely-accepted candidates for the kingship, hit upon a candidate in the person of Conchobar Ua Briain, grandson of Toirdelbach's uncle Donnchad mac Briain and Toirdelbach's most obvious rival for the kingship of Munster. Conchobar was king for only a short time when he was murdered, along with his wife. His brother Cennétig was chosen to succeed him.

In Connacht, three rival branches of the Uí Briúin, the Ua Conchobair, the Ua Flaithbertaig, and the Ua Ruairc, were in competition. Ruaidrí na Saide Buide of the Ua Conchobair was king of Connacht when he submitted to Toirdelbach in 1076. Toirdelbach deposed Ruaidrí in 1079 and replaced him with an Ua Ruairc, Áed son of Art Uallach.

The Ua Ruairc proved to be a threat to Toirdelbach and to their neighbours. Máel Sechnaill, king of Mide, submitted to Toirdelbach in 1080, perhaps for fear of Ua Ruairc. War broke out in 1084 between Toirdelbach and the Ua Ruairc, joined by Cennétig Ua Briain. Toirdelbach raided Mide, but while he was absent the Conmaicne, clients of the Ua Ruairc, raided Munster. A battle was fought at Monecronock, near modern Leixlip, on 19 October 1082 where Toirdelbach's sons Muirchertach and Tadc won, killing Domnall Ua Ruairc and Cennétig Ua Briain.

Death

Toirdelbach fell seriously ill in 1085 and lost his hair. The Annals of the Four Masters, a late and not always reliable source, state that he had been ill for many years. He may never have fully recovered from his earlier illness. The Annals of Ulster report that he "died in Kincora [near Killaloe] after great suffering and long repentance, and after receiving the Body of Christ and His Blood, on [14 July] in the seventy-seventh year of his age [1086]". Rarely given to over-praising southern kings, this northern annal calls him "king of Ireland". The Annals of Tigernach, another northern record, styles Toirdelbach rí urmóir Erenn, "king of the greater part of Ireland".

Toirdelbach was probably married three times. Dubchoblaig of the Uí Cheinnselaig, who died in 1088, was the mother of Diarmait, perhaps named for her kinsman and Toirdelbach's protector Diarmait mac Maíl na mBó. Derbforgaill of Osraige was the mother of Tadc and Muirchertach. No children of Gormlaith of Ua Fógarta are named and the mother of Toirdelbach's daughter Mór is not recorded.

Mór married Ruaidrí na Saide Buide. Her son Toirdelbach Ua Conchobair was one of the greatest kings of medieval Ireland. She died in 1088, perhaps coincidently the year in which a gloss to the Annals of Ulster records Toirdelbach's birth. Toirdelbach apparently planned to divide his lands between his three sons. Tadc survived him by only weeks, dying of natural causes at Kincora, after which Muirchertach and Diarmait disputed the succession. Diarmait was the loser, banished by his half-brother, and exiled with his mother's kin in Leinster.

Toirdelbach — Derbforgaill of Osraige. [Group Sheet]