numerous: South East, Mayo, Galway etc. Ir. de Breit. "Le Bret" Norman term for Bretons, who were present in the invasion of 12 cent. MIF & SI.
rare: Dublin. Anglo-Normans of Breton origin who settled in various parts of the country. More usually Brett, Ir. de Breit. The use of the name by the Anglo-Saxons to describe the Strathclyde Britons and the Welsh is discussed by Reaney. DBS.