Near the monastery of Clonmacnoise are the ruins of the “Nuns’ Church” completed by Dervorgilla in 1167. Dervorgilla was the daughter of Murchad Maelseaclainn (Ua Máelsechnaill), king of Meath (Mide), which was the fifth and richest province of Ireland, stretching from the sea at Drogheda to the Shannon and including the modern counties of Meath and Westmeath together with parts of Kildare, Offaly and Laois. She was the wife of Tiernan O’Rourke (Ua Ruairc), prince of Breffni (Bréifne). One day in 1152 Tiernan O’Rourke returned from a pilgrimage to the holy island of St Patrick on Lough Derg and realised that Dervorgilla was gone. He learned from the servants that a small group of horsemen had taken Dervorgilla, her cattle and her furniture. From their description, he realised that the leader of the group was his enemy, the King of Leinster Diarmait McMurrough. Tiernan O’Rourke sought the help of the High King, Turlough O’Connor (Ua Conchobhair). O’Rourke explained that McMurrough had abducted his wife and taken her to his stronghold at Ferns. Turlough O’Connor and Tiernan O’Rourke raised an army, invaded Leinster and recovered Dervorgilla. McMurrough was banished and fled to Bristol. He would later return with the Anglo Normans to recover his kingdom.
It has never been clear whether Dervorgilla was really abducted (it seems unlikely that a kidnapping would include her cattle and furniture) or whether she willingly ran away with a person who was believed to have been her lover for many years. What is certain is that the apparent abduction of Dervorgilla triggered a series of events that had a significant impact on Irish history. The most important of these was the Anglo Norman invasion of Ireland.
Dervorgilla died at Mellifont on 25 January 1193. She was 85 years old and had outlived all the participants in the events of 1152 by many years.