Domhnall Caomhánach

Domhnall Caomhánach was the eldest son of Diarmait Mac Murchada, king of Leinster, and the first man to carry the name Caomhánach. Irish custom recorded that he took the byname because he was fostered and trained at the monastery of Saint Cóemgen at Kilcavan in County Wexford, making him a student or follower of that saint. What began as a personal marker of his upbringing became an inherited surname for his descendants, linking a royal family to a small monastery and a merciful saint.