Background: From the County of Donegal, Ireland. The name is occasionally made Bohill in County Down. The famous Boyle, Earl of Cork, was of an old English (Hertfordshire) family. BOYLE Boyle, or O’Boyle, is now one of the fifty most common surnames in Ireland. In Irish the name is O’Baoghill, the derivation of which is uncertain, but thought to be connected to the Irish geall, meaning ‘pledge’. In the Middle Ages the family were powerful and respected, sharing control of the entire northwest of the island with the O’Donnells and the O’Dohertys, and the strongest association of the family is still with County Donegal, where (O)Boyle is the third most numerous name in the county. The majority of those bearing the name are of Gaelic origin, but many Irish Boyles have separate, Norman origins.