Britonia was established in the GermanicKingdom of the Suebi, in the Roman Gallaecia, northwestern Hispania, in the late 5th and early 6th centuriesAD by Romano-Britonsmoving away from the Anglo-Saxons, who were conquering Britain. Britonia is therefore similar to Brittany in Gaul, in that it was settled by expatriate Britons at roughly the same time. Britons may have occupied a pre-existing Celtic hill fort or castro. Gallaecia had earlier been inhabited by Celts, before the arrival of the Germanic Suebi. Modern place-names that reflect this history include the villages of Bretonia in the province of Lugo and Bretoña in the province of Pontevedra.
Ecclesiastical history
What little is known of Britonia is deduced from its religious history. The British settlements were recognised at the First Council of Lugo in 569 and a separate bishopric established, on territory split off from the then Metropolitan Archdiocese of Lugo. Mailoc was nominated Bishop of Britonia and signed the acta at the Second Council of Braga in 572. The British Celtic settlements were quickly integrated and their adherence to Celtic rite lasted only until the Fourth Council of Toledo in 633 decreed the now so-called Visigothic or Mozarabic rite as the standard liturgy of Hispania. The diocese was suppressed in 716. The line of bishops of Britonia nevertheless existed at least until 830, when the area was attacked by the Vikings; it may have continued as late as the Council of Oviedo in 900. It was finally restored as or merged into the Diocese of Mondoñedo-Ferrol in 866, being assigned territories split off from the Diocese of Oviedo and from the Metropolitan Archdiocese of Lugo.
Resident Bishops of Bretoña
Known bishops of the ecclesia Brittaniensis include:
No longer a residential bishopric, Britonia is today listed by the Catholic Church as a titular see. The diocese was nominally restored in 1969 as Latin Titular bishopric of Britonia / Britonien. It has had the following incumbents, so far secular priests of the fitting Episcopal rank:
Eugene O’Callaghan, on emeritate as former Bishop of Clogher , died 1973