Derbforgaill (1108-1193), daughter of Murchad Ua Maelsechlainn, king of Mide, and wife of Tigernan Ua Ruairc, king of Breifne, owes her place in history mainly to her abduction at the hands of Diarmait Mac Murchada, king of Leinster. Following an internal Leinster rebellion against Mac Murchada more than a decade after the abduction, Ua Ruairc seized the chance to avenge his insulted honor and marched on Mac Murchada, expelling the Leinster king across the Irish Sea. Mac Murchada’s subsequent recourse to foreign military aid in regaining his kingdom brought about the Anglo-Norman invasion. Surveying this chain of events, contemporary and later observers laid the blame for the invasion at Derbforgaill’s feet, dubbing her the Irish Helen of Troy. Different sources have attributed varying motivations for the abduction, including revenge and overweening lust. Given the circumstances surrounding the kidnapping, however, which occurred in Mide in 1152 following Tigernan’s temporary deposition as king of Breifne by Diarmait and Tairrdelbach Ua Conchobair, it is likely that political motivations were at least partly at play. Mac Murchada and Ua Ruairc were competitors in the territorial dismemberment that took place in Derbforgaill’s homeland of Mide following that kingdom’s twelfth-century collapse as a major power. In addition to representing a dramatic undermining of Ua Ruairc’s authority, it has accordingly been suggested that Derbforgaill’s seizure may have symbolized Mac Murchada’s pretensions toward Mide. Some sources report that Derbforgaill’s brother Mael-Sechnaill colluded with Mac Murchada in arranging the abduction; possibly Mael-Sechnaill, who had newly come into power in the eastern portion of Mide, felt his best chances for survival lay in an alliance with Mac Murchada. Derbforgaill’s own role in the kidnapping has been a further matter of dispute, with some sources portraying her as an innocent victim led to the kidnapping site by her brother. Others, no doubt influenced by the report that Derbforgaill was accompanied into captivity by all her cattle and her wealth, accuse her of having been complicit in the affair. Complict or not, however, through the intervention of Tairrdelbach Ua Conchobair, Derbforgaill, her cattle, and her wealth returned to Ua Ruairc within the year.
That wealth must have been fairly considerable, for in 1157 Derbforgaill is recorded as donating a large sum of gold to the newly consecrated monastery of Mellifont in Drogheda. While Mellifont had links to Ua Ruairc, Derbforgaill was also a generous patron of churches associated with her own family. In 1167, she finished the Nuns Church at Clonmacnoise, a foundation linked to the Arroasian convent at Clonard where her cousin Agnes was abbess. Derbforgaill retired into religious life in Mellifont in 1186, dying there seven years later at the age of eighty-five. Although she is the single most historically documented woman in pre-Norman Ireland, there is no record of Derbforgaill’s having had any children. The fact that Tigernan had a son called Mael-Sechnaill, a name with strong family links to Derbfor-gaill not hitherto seen in the Ua Ruairc genealogies, may, however, indicate she had at least one child.
