clonmacnoise monastery

Clonmacnois Monastery was founded in 548-49 by St. Ciaran, after abandoning his cell on Hare Island in Lough Ree. Dermot, a local prince, enlisted Ciaran's prayers to get him elected High King. Dermot rewarded Ciaran by endowing the monastery. Ciaran died shortly afterwards, but Ciaran's monastery prospered.
One interesting church in the monastery is the Nuns' church which was erected, by Queen Devorgilla as a mark of repentance in 1167. In 1152, Devorgilla deserted her husband, Tiernan O'Rourke, while on pilgrimage to Lough Derg. To add insult to injury, she eloped with his worst enemy Diarmuid MacMurrouhg, bringing her animals and furniture with her. She returned to her husband and spent the rest of her life involved in church works.
The monastery suffered under the Vikings, particularly in 844, when it was burned by Turgesius and his wife Ota, who then performed "heathen oracles" on the altar.