BACKGROUND: Derbforgaill and the expulsion of Diarmait Mac Murchada

Published in Features, Issue 3 (May/June 2019), Volume 27

Did she elope? Was she abducted? A scarlet woman responsible for Ireland’s woes or a tragic victim who personified her country? The so-called ‘Rape of Dervorgilla’ has played a prominent role in the historiography of the 1169 invasion, but who was she?

By Denis Casey

With, for a husband, a ‘one-eyed king, nursing villainous treachery’, and a suitor who was given to ‘insatiable, carnal and adulterous lust’, it is little wonder that the story of the abduction of Derbforgaill, queen of Bréifne, and its place in the events leading to the invasion of Ireland have retained a hold on the imagination. From Irish playwrights such as Lady Gregory to American poet-presidents like John Quincy Adams, the contested story of Derbforgaill’s abduction/elopement has proved fertile ground for repeated interpretation and manipulation, encouraging everything from explorations of gendered blame for Ireland’s colonial history to moral lessons for the preservation of a state’s freedom by a virtuous citizenry. Many of the treatments of Derbforgaill’s story have an understandably contemporary (and frequently anachronistic) focus, but who was Derbforgaill and what do the earliest sources tell us about the single incident in her long life for which she is remembered?

Derbforgaill’s abduction in context

Derbforgaill (c. 1108–93) was a daughter of Murchad Ó Maíl Shechnaill, king of Mide (mainly Meath and Westmeath), and was married to Tigernán Ó Ruairc, king of Bréifne (on Mide’s northern borders). Her family’s kingdom was a declining power and during her lifetime the two major contenders for the high-kingship of Ireland (Tairdelbach Ó Conchobair of Connacht and Muirchertach Mac Lochlainn of the North) frequently partitioned it between rival claimants in an effort to create a political settlement to their liking. On the ground, her husband and his half-brother (Donnchad Ó Cerbaill of Airgialla, to Mide’s north-east) gradually chipped away at it too.

Her husband’s geographical position required him to be politically nimble, but by 1152 both Mac Lochlainn and Ó Conchobair had had enough of Ó Ruairc’s constant changing of sides and they teamed up with Diarmait Mac Murchada of Leinster to depose Tigernán from the kingship of Bréifne and divide Mide (yet again) between Derbforgaill’s father and brother. On that occasion Mac Murchada extraordinarily took Derbforgaill and her goods back with him to his patrimony of Uí Chennselaig in south Leinster. But Tigernán Ó Ruairc was not finished yet. He probably exploited Mac Lochlainn’s and Ó Conchobair’s rivalry to engineer his own restoration and, with the help of the latter, Derbforgaill was also restored to him in 1153. Thirteen years later Mac Lochlainn and Ó Conchobair were both dead and Mac Murchada was largely friendless. Tigernán (probably with the connivance of his ally and son-in-law Ruaidrí Ó Conchobair, undisputed high-king of Ireland) brought together a military coalition that attacked Mac Murchada and caused him to flee overseas. On his return in 1167, Mac Murchada was forced to pay compensation to Tigernán for the slight put upon his honour by the abduction of his wife, but in every sense the damage was already done. So far the story is seen through the medieval Irish annals.

The medieval sources

From the invaders’ perspective, the story is told in the anonymous Norman-French ‘The Song of Dermot and the Earl’ and in the Latin Expugnatio Hibernica (‘The Conquest of Ireland’) by Gerald of Wales (Giraldus Cambrensis). Both were written in the decades immediately following the invasion and they both assign to Derbforgaill a willingness to be abducted (although in the ‘Song’ she is a dupe of Mac Murchada). Significantly, both telescope the events of the 1150s and 1160s to make it appear as if Mac Murchada’s banishment was a direct and immediate result of the abduction (in 1152) rather than occurring fourteen years later (in 1166).

The principal Irish sources are the largely contemporary annals, which are not given to highlighting cause and effect, and while the Anglo-Norman sources laid the blame for her abduction in part at least at Derbforgaill’s door, the annals do not. In addition, other medieval Irish sources, such as the rich corpus of bardic poetry dating from the early thirteenth century onwards, are generally silent about Derbforgaill when touching on the invasion. It is not until the early modern period that she becomes something of a villain—most notably in Geoffrey Keating’s enormously influential Foras Feasa ar Éirinn (‘History of Ireland’). Keating claimed that it was she who arranged the abduction but ‘wept and screamed in pretence, as if Diarmaid were carrying her off by force’, affording her plausible deniability and fooling her husband as to her intentions, with fateful consequences. Yet Keating’s account was highly reliant on Gerald of Wales (however much he might have hated him), and ultimately it appears that Derbforgaill’s complicity was a product of medieval Anglo-Norman historians, which only later filtered into Gaelic sources.

Modern historiography

Modern historians have tended to shy away from personality-based interpretations and instead place the abduction in the broader context of rival territorial ambitions in the midlands, namely the desires of Derbforgaill’s husband and her abductor to expand their kingdoms at the expense of her paternal kin (Uí Maíl Shechnaill), who were sandwiched between the two and struggling for survival. Certainly Tigernán Ó Ruairc busied himself in salami-slicing Mide from the north (see ‘Tigernán Ua Ruairc and the Book of Kells’, HI 18.5, Sept./Oct. 2010), but Mac Murchada was not as active or as successful in the midlands as he is sometimes given credit for. He was a recipient of territory in east Mide when it was partitioned in 1144 (actually sharing it with Ó Ruairc), but the arrangement did not even last a year and there is little evidence to suggest that he was as effective as Ó Ruairc in expanding his borders. Even when Mac Lochlainn and Ó Conchobair teamed up to depose Ó Ruairc and repartition Mide in 1152 there was no share for Mac Murchada, and in 1153 Mac Lochlainn even went so far as to strip him of portions of north Leinster in order to shore up his nominee to the kingship of Mide, Derbforgaill’s brother. For all his efforts—as would happen again in 1166—Mac Murchada ‘got no glory save the corpses of the Uí Cennselaigh’ (Annals of Tigernach). In short, despite obtaining a stranglehold on Dublin in the 1160s, Mac Murchada’s midlands ambitions were a busted flush even before the abduction. If his actions in 1152 are to be viewed as part of the ballet of midlands politics, they were those of a frustrated and disappointed actor and might even be interpreted as an act of pique.

Where all this leaves Derbforgaill is unclear, but she appears to have returned and remained married to Tigernán Ó Ruairc and was present alongside him at the consecration of the church of Mellifont (1157), which they both endowed generously (implying a sense of unity between them) and where she eventually died (1193). In addition, if aristocratic marriage is primarily a means of forging alliances and producing offspring, then she should have been surplus to requirements for Ó Ruairc; she was probably past child-bearing age and already by the mid-1150s the kingship of Mide (or active claim to it) had passed from her brothers to her nephews, reducing her utility as a political bridge. Ó Ruairc’s extraction of compensation from Mac Murchada over a decade down the line and the endurance of Tigernán and Derbforgaill’s marriage until his death (1172) all hint at a stable relationship and may cautiously be taken as circumstantial backing for supposing that she was indeed abducted and did not elope.

Denis Casey teaches on the Critical Skills programme at Maynooth University.


A. MacShamhráin, ‘Derbfhorgaill (c. 1108–1193)’, in J. McGuire & J. Quinn (eds), Dictionary of Irish biography from the earliest times to the year 2002 (9 vols) (Cambridge, 2009), iii, 175–6.

J.V. Ulin, ‘“Can a wrong once done ever be undone?” Ireland’s Helen of Troy’, Women’s Studies Quarterly 39 (3–4) (2011), 173–92.


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