Ancient Kildare & The Kings of Leinster - IntoKildare
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Ancient Kildare & The Kings of Leinster


Ireland’s early history is wrapped in legends that resound within the culture today. Sacrificing a neighbour’s son to the Sun god, fighting with and against the Vikings, kneeling before a Celtic cross – these are the stories of Ireland’s legendary yet pragmatic High Kings…

‘In the plain of Kildare stood that monstrous heap of stones, brought thither by gyants from Afrique, and removed thence to the plain of Salisbury, at the instance of Aurel Ambrose, king of Britain.’[i] So declared the Jesuit historian Edmund Campion in 1571, alluding to the legend that the mighty bluestones used to form the stone circle of Stonehenge in England had been spirited across the Irish Sea from Kildare by no less a soul than Merlin the magician. Far-fetched, assuredly, and yet there is something so extraordinarily mysterious about Kildare’s ancient past that even fictitious wizards must be treated with respect.


It is generally reckoned that the first humans settled in Ireland at the close of the last ice age 12,000 years ago. As the ice melted, so the glacial melt-water rushed down the slopes of the Wicklow Mountains, carrying sand, gravel, boulder clay and other layers of sediment. Some spread over the massive open space that now form the 4,780-acre Curragh to create what is presently regarded as one of the finest alluvial plains in Europe.

The peat bogs of the Bog of Allen were simultaneously formed and shaped by a vast glacial lake; antlers and bones of the Irish Elk (also known as the ‘Great Irish Deer’) were found near Rathcoffey Hill on what was once the shore of this lake.

The earliest evidence of mankind in County Kildare is found on the Curragh plain, where the Stonehenge rocks are said to have lain, and where some forty-four sacred sites have been identified. Many of these date back to the Neolithic period of between 4000 and 6,000 years ago, including a number of circular raths, or henges, surrounded by banks and ditches. The biggest of these is the Gibbet Rath, which boasts an enclosure with a diametre of over 100 metres. The Curragh is also home to one of Ireland’s largest concentration of barrow-graves, or tumuli.[i]

The epochs of both the Bronze Age and the Iron Age are marked on the Curragh, most notably at the 13-hectare circular hill-fort of Knockaulin (Cnoc Ailinne), or Dún Ailinne, on its north-eastern edge, near Kilcullen. Initially built in the late Neolithic period, this was a site of assembly through the Iron Age and is thought to have been where the Kings of Leinster were inaugurated, as well as a ceremonial site. To its west, bogs marked the ancient borderland between the provinces of Laigen (Leinster) and Midhe (Meath) while the Curragh rolled eastwards towards the Wicklow Mountains.

Such landscapes come to life in the annals where the “Curragh of the Liffey” is noted as the setting for the annual Aenach Lifé fair, at which the warriors and sportsmen of Celtic Ireland gathered for chariot racing, wrestling matches and other games.[iv]

The ‘Longstone of Punchestown’, a 23-foot high stone that stands 600 metres from the entrance to the racecourse, is the second highest such stone in the British Isles. While initially thought to have signalled a meeting point for sporting occasions, a Bronze Age burial site discovered nearby contained the cremated remains of four people.

Similar grooved granite long stones, unique to Kildare, have been found at Ballycore, Craddockstown, Mullaghmast, Harristown, and Forenaghts Great. The latter featured a trapezoidal cist in which cremated human remains were found, along with pottery and a fragment of a wrist-guard from the Beaker period of 2450–1900 BC.[v]

Legend holds that the Punchestown Longstone was hurled into position by the hunter-warrior Fionn mac Cumhaill during a stone-throwing contest that took place on the Hill of Allen (Cnoc Alúine), 20km west. The hill features in the saga Fotha Catha Cnucha (“The Cause of the Battle of Cnucha”) when Cathair Mór, a Leinsterman who became High King of Ireland, gifted it to the druid Nuada, who was Fionn’s great-grandfather. The Hill of Allen was the mythical Fionn’s birthplace as well as his fortress; the contiguous flatlands served as a training ground for his band of Fianna warriors.

The Curragh plains famously provided the location for the key battle scenes in the Oscar-winning movie ‘Braveheart’ but the annals are replete with battles that took place here and elsewhere in County Kildare during distant days. One of the earliest took place in ‘the year of the world 4608’ when Laoghaire Lore, ‘King of Ireland’, was slain on the Curragh by his own brother.

Moving to rather more recent times, Athy or Baile Átha Í (“the town of Ae’s ford”) is named after the warrior Ae who was killed in a battle on the Barrow River crossing in the 2nd century AD. A standing stone at Knockbaun is said to mark the site of the battle.

Clane is thought to have been the setting for the Battle of Claenath in 704 AD in which Cellach Cualann, the Uí Máil king of Leinster, routed an invasion by the northern Uí Néill and killed their leader [vi]. The death of King Cellach’s son Áed mac Cellaig at the Battle of Finnabair (Fennor, Co. Kildare) fifteen years later spelled the end for the once dominant Uí Máil dynasty.[vii]

Rathangan is home to one of the most remarkable ringforts in Ireland, an extensive tree-flanked platform rath which stands close to the chapel. The forts longevity is such that it was celebrated in one of the earliest Irish poems, an eighth-century ode to the endurance of such earthen works:

“The fort opposite the oakwood,
Once it was Bruidge’s, it was Cathal’s,
It was Ard’s, it was Ailill’s,
It was Conaing’s, it was Cuiline’s,
And it was Maelduin’s.
The fort remains after each in his turn,
And the kings asleep in the grounds.”

Among scores of other ringforts found in the county are those at Raheen (a ring barrow near Rathcoffey), Woodlands West (near Castledermot), Fontstown Upper and Mullaghmast, while numerous other dwellings, trackways, cremation pits, fulacht fiadh and souterrains have also been found.

One of the biggest battles in Irish history took place around the Hill of Allen in 722 AD when the Leinstermen defeated an army of Uí Néills and killed the High King of Ireland. Murchad mac Brain Mut, the victorious King of Leinster, hailed from the Uí Dúnlainge branch of the Laigin.[viii]

The Uí Dúnlainge’s rise to power was further increased by the annihilation of their Uí Cheinnselaig rivals at the Battle of Groans (or the Battle of Áth Senaig) in 738AD. The Uí Cheinnselaig king was among those killed by forces loyal to Áed Allán, the High King of Ireland, in a gruesome clash that is thought to have taken place at Ballyshannon, between Calverstown and Suncroft. According to the Annals of Ulster: ‘… men say that so many fell in this great battle that we find no comparable slaughter in a single onslaught and fierce conflict throughout all preceding ages.’[i]

The demise of the Uí Cheinnselaig paved the way for the Uí Dúnlainge who a vice-like grip over the kingship of Leinster for the next three centuries, although there was much in-fighting as the throne rotated between three septs within the dynasty itself. These three septs were the Uí Muiredaig of Mullaghmast [Máistín] who provided 14 kings and later became the O’Toole family; the Uí Faelain of Naas who provided 9 kings and later became the O’Byrne family; and the Uí Dúnchada of Lyons Hill [Líamhain) on the Dublin-Kildare border, who provided 10 kings and became the FitzDermots.

The Uí Dúnchada, who had their inauguration site at Lyons Hill, also held the Abbacy of Kildare during this time, a lucrative and powerful office given that this was the age in which the cult of St Bridget was at its peak. [x]

The Uí Fáeláin kings of Leinster ruled from their stronghold at Naas, or Nás na Ríogh, ‘the place of kings’. The last to do so was Cerball mac Muirecáin, “a skilful  horseman”, who expelled the Norse from Dublin City in 902 AD. Six years later, he took part in the Battle of Bellaghmoon in which his saintly foster brother, King Cormac of Munster, was killed.[xi] Afterwards Cerball was escorting a group of prisoners through Kildare but, as they rode passed a blacksmiths forge on Chéime Cloiche [Street of the Stone Step], his horse shied and flung him on to his own lance.[xii] The wound proved fatal and he died a year later, having spent most of the intervening period in Naas. He was buried in Cill Corban, or the Church of Corban, at Kill, as were eight previous Kings of Leinster before him.[xiii]

One of the greatest battles of the Viking Age was fought close to Lyons Hill when the celebrated Brian Boru destroyed a combined Leinster-Viking army in the battle of Glenmama, enabling Boru to capture Dublin City on New Year’s Day 1000.[xvi] Three years later the last of the Uí Dúnchada kings of Leinster was deposed by Máel Mórda of the Uí Fáeláin.[xv] Máel Mórda would die in the epic battle with Boru at Clontarf in 1014 and his son Bran mac Máelmórda was, in turn, the last of the Uí Fáeláin kings of Leinster.

Donnchad mac Dúnlainge, the last Uí Muiredaig king – and by extension the last of the Uí Dúnlainge kings – died in 1033.[xvi] The Uí Muiredaig’s base was on the hill of Mullaghmast in south Kildare. Legend holds that this impressive rath was the home of Maistiu, the wife of Dáire Derg, who was killed by the sorcery of the malevolent fairy Gris. A pillar-stone found in the rath and decorated with a triskele is thought to be at least 1600 years old and possibly a good deal older; the Mullaghmast Stone is now held by the National Museum of Ireland in Dublin. Intriguingly the rath at Mullaghmast lies approximately the same distance from Naas as Knockaulin, or Dún Ailinne, and both are very nearly on the same alignment.[xvii] Among the other thirteen Uí Muiredaig kings of Leinster was Augaire mac Ailella whose army was crushed by Norse Dubliners at the Battle of Confey (or Cenn Fuait) near Leixlip in 917 AD, thus enabling the Norse to recapture Dublin fifteen years after their expulsion by King Cerball.

Ancient Kildare & The Kings of Leinster is by Historian and Author Turtle Bunbury.

[1] ‘Historie of Ireland, Written in the Yeare 1571’ by Edmund Campion (Hibernia Press, 1809). The story first appears in printed form in 1136 when the Welsh cleric Geoffrey of Monmouth published Historia Regum Britanniae (The History of the Kings of Britain’), a largely fictitious book that was treated as utterly credible for many long centuries. It was Geoffrey who made the bold claims was that the mighty bluestones used to form the stone circle of Stonehenge in England came from a place known as the Giants’ Ring on “Mount Killaraus” in Ireland. In Arthurian lore, Uther Pendragon, the father of King Arthur, sailed for Ireland with fifteen thousand men to collect the rocks. When they proved unequal to the task, Merlin the magician used his sorcery to spirit them across the Irish Sea to the Salisbury Plains where they stand today. There is no other record of anywhere called Mount Killaraus but, curiously, John O’Donovan, an exceptionally bright nineteenth century Irish cartographer and scholar, recorded ‘certain stones on the plain of Kildare’ that were ‘in every respect similar to the others and erected in a similar manner’ However, as O’Donovan lamented, “There is no doubt…that such stones existed … either near the Castle of Kildare or that of Naas, but I fear they have been long since destroyed.”

[1] A series of earthworks on the Curragh, originally excavated in 1944, appear to have been important locations for burials and other deposits. One possible [?] multivallate ring-barrow revealed a long pit containing the extended skeleton of an adult; the pit was covered by a small mound and surrounded by a pair of concentric ditches with diameters of about 12m and 18m respectively, each possibly having an external bank. The burial has not yet [CHECK] been dated. 

In a stone-henge at the Curragh, archaeologists found a pit containing the skeleton of a young woman buried alive.

[1] As a ceremonial site, it is certainly connected to the large number of ring-barrows, enclosures and linear earthworks on the Curragh. The bulk of the animal bones found on the site were pig and cattle (primarily young calves, slain in spring soon after their birth, or in autumn, aged about six months) although some horse, dog and sheep bones were also found. The embanked ring-ditches on the Curragh were party excavated. One, situated at the highest point in the area, was about 45m in overall diameter with an entrance on the west; a second, about 35m in overall diameter with entrances on the east and west, enclosed the unburnt burial of an adult female in a central pit which was believed to be an instance of burial alive; and the third, over 28m in diameter, had one entrance on the south west. None produced any dating evidence. See: John Waddell, The Prehistoric Archaeology of Ireland (Galway University Press, 1998), p. 392.  

In 2008, an interpretative site was opened at Nicholastown, a townland just south of Kilcullen, featuring a bilingual information panel (Irish and English) and a small-scale reproduction of the mound, topped by a sculpture.

“The whole site is on private farmland and casual access is restricted due to difficulties with livestock; in general, the owners of the land have no problem with people having a stroll as long as they ask permission beforehand at the farmhouse just on the north-east side of the hill beside the N78 road.” (Wikipedia, 29 july 2016).

[1] “The most important notice is contained in the historical tale of the destruction of the mansion of Dá Derga. In this,Connairé Môr, who was killed A.D. 60, is represented as having gone to the games at the Curragh with four chariots. From this and other sources we may conclude, that chariot-races preceded horse-races in ancient Erinn, and that the Curragh has been used as a place of public amusement for the last 2,000 years.” Sister Mary Frances Clare, ‘An Illustrated History of Ireland’, Chapter XV, via

[1] Other Bronze Age graves have been found in places such as Moone, Carbury Hill, Forenaughts Great, Blackhill, Brownstown, Granby West, Oldtown, Poopluck – and even under the front lawn of Castletown House

[1] In 704AD Cellach Cualann, the last Uí Máil king of Leinster, routed an invasion by his northern neighbours, the Uí Néill of Clann Cholmáin at the Battle of Claenath, near Clane. Bodbchath mac Diarmata Déin, the Uí Néill leader, was killed while Fogartach mac Néill, commander of the Síl nÁedo Sláine, fled the field of battle. Fogartach later became king of Brega, a petty kingdom north of Dublin, and was briefly High King of Ireland before he too was slain in battle.

[1] In 719AD, Áed mac Cellaig, a son of Cellach Cualann, the last Uí Máil king of Leinster, was slain at the Battle of Finnabair (Fennor, Co. Kildare) in a fight among the Laigin. The death of his younger brother Crimthann mac Cellaig at the Battle of Belach Lice in 726AD (at “an immature age”, according to the Annals of Ulster), brought the Uí Máil dynasty to an end.

[1] The Battle of Allen was fought on 11 December 722 AD. The Leinstermen, commanded by King Murchad mac Brain Mut, fought off a large invasion by the northern and southern Uí Néill, commanded by Fergal mac Máele Dúin, the High King of Ireland since 710. Fergal fought alongside his son Aedh Allen, and Aedh Laighean, King of Uí Maine in Connacht, but it proved to be a disaster for the High King who was killed alongside numerous nobles of the Ui Neill. Such a famous victory did much to cement the Uí Dúnlainge branch of the Laigin, from which Murchad hailed, as a rapidly rising powerhouse. The battle was preserved in the 10th century saga Cath Almaine. The site is currently part-owned by Roadstone Dublin Ltd.; the hill has been extensive quarried since.

[1] In 738AD the Leinstermen suffered a major defeat at the Battle of Áth Senaig (Ballyshannon, Co. Kildare), also known as the Battle of Groans, when the high king Áed Allán, of the Cenél nEógain, destroyed the Uí Cheinnselaig and killed their king, Áed mac Colggen.

[1] The Uí Dúnchada were one of the three Uí Dúnlainge septs, which rotated the kingship of Leinster between 750 and 1050. The Uí Dúnchada descend from Dúnchad mac Murchado who succeeded as King of Leinster following the death of his father Murchad mac Brain Mut in 727AD. Later that year Dúnchad defeated and killed his Uí Cheinnselaig rival Laidcnén mac Con Mella, at the Battle of Maistiu or Mullaghmast. However, Dúnchad, was slain by his younger brother in 728 who duly claimed the throne for himself. Dúnchad’s son Cellach mac Dúnchada was King of Leinster from 760 until his death in 776.

In 590 AD, Brandub mac Echach, a future king of the Uí Cheinnselaig of Leinster, had his first taste of victory the Battle of Mag Ochtair [near ‘Cloncerry’, which is thought to be near Lyons?] He was later assassinated by his own kinsman and son-in-law.

[1] On 13 September 908, the Battle of Bellaghmoon [Bealach Mugna / Moone] was fought near Castledermot between an army led by Cormac mac Cuilennáin, the saintly king of Munster, against the allied forces of Flann Sinna, the venerable High King of Ireland, as well as the kings of Leinster and Connacht. King Cormac was hailed in the Annals as ‘a scholar in Irish and in Latin, the wholly pious and pure chief bishop, miraculous in chastity and in prayer’, and his works are said to have included the Sanas Cormaic (Cormac’s Glossary), and the now-lost Psalter of Cashel. The Annals of the Four Masters claim he was tutored by Snerdgus, Abbot of Díseart Díarmata (now Castledermot). Bellaghmoon was to prove his downfall. The Munster men were unwilling to fight, spooked by the ill-omen of Flaithbertach, Cormac’s sinister advisor and abbot of Inis Cathaig (Scattery Island), tumbling from his horse at the muster. It was a decisive victory for Flann and his allies. Cormac was among those who died, his neck broken after a fall from his horse. His head was subsequently presented to Flann Sinna but, according to the Fragmentary Annals, the High King was unimpressed. ‘“It was an evil deed,” he said, “to cut off the holy bishop’s head; I shall honour it, and not crush it.” Flann took the head in his hands, and kissed it, and he carried the consecrated head and the true martyr around him three times.’ Cormac was buried at Díseart Díarmata where his shrine was said to be the site of miracles. He appears in a stained glass window in St Patrick’s Cathedral, Dublin, designed by Sarah Purser and painted by Alfred Ernest Child. As for Flaithbertach, he was taken to Kildare and held prisoner where he was subjected to much abuse for poisoning the mind of the saintly King Cormac by Muirenn ingen Suairt, the abbess of Kildare. That said, he somehow made it back to Cashel wheée he was installed as king of Munster in 914.

[1] Journal of the County Kildare Archaeological Society, County Kildare Archaeological Society, Vol. III (July 1899-1902), p. 124-125 @

[1] Afterwards Cerball was escorting a large number of prisoners to Kildare on ‘a spirited horse’. As they rode through the street called Srait in Chéime Cloiche [Street of the Stone Step], they passed the workshop of ‘a fuller’. Cerball’s horse shied and flung him on to his own lance, which his Norse gillie Ulfr was carrying behind him. The wound proved fatal and he died a year later, having spent most of the intervening period in Naas. He died on 19 September 909 and was buried in Cill Corban, or the Church of Corban, at Kill, as were eight previous Kings of Leinster before him. He apparently married Cormac’s widow (or possibly fiancée) Gormfalth but they were separated after he offered her “a gross insult”.

[1] On 30 December 999AD, the Leinstermen united with the Norse of Dublin to fight against Brian Boru, King of Munster, and Máel Sechnail. They met at Glenmama, a site to the east of Oughterard Hill adjoining Lyons Hill, between Castlewarden, Windmill Hill and Blackchurch, the ancient stronghold of the Kings of Leinster. [Check] The victory of the Munster-Meath army not only crushed the Leinster-Dublin alliance but also left the road to Dublin utterly free for Boru’s victorious legions to sweep in and capture the city on New Year’s Day 1000.

[1] The Uí Fáeláin, one of three septs of the Ui Dúnlainge, ruled over the Airthir Liphi, the eastern part of the Liffey plain, during the eight and ninth centuries. The sept was founded by Fáelán mac Murchado, a younger son of Murchad mac Brain Mut, King of Leinster, who defeated and killed his older brother Dúnchad at the Battle of Ailenn in 728AD, and so secured the throne of Leinster, as well as Dúnchad’s widow, who he promptly married. Fáelán’s son Ruaidrí mac Fáeláin, who died in 785AD, was also King of Leinster.

[1] Within a decade of King Donnchad’s death, the Uí Cheinnselaig of Ferns had resumed control of the kingdom of Leinster. Diarmait mac Maíl na mBó, the first of this new line, played host to Harold Godwinson’s exiled sons in the wake of the Norman victory at the battle of Hastings in 1066. King Diarmait’s great-grandson was the Dermot MacMurrough, King of Leinster, who “invited” the Anglo-Normans to conquer Ireland in 1169.

[1] Susan A. Johnston, Bernard Wailes, “Dun Ailinne: Excavations at an Irish Royal Site, 1968-1975” (University of Pennsylvania Press, 2011), p. 186 –
AI#v=onepage&q=%22Maistiu%22&f=false – this is an important source.