Dictionary of National Biography, 1885-1900/Bega
BEGA (8th cent.?) was a saint whose history is wrapped in much obscurity, and has been much mixed up with that of others. According to Butler (6 Sept.) she was an Irish virgin (7th cent.) who lived as an anchoret, and founded a nunnery in Copeland. Leland (Coll. iii. 36) follows another version, according to which, after founding her monastery in Cumberland, she passed into Northumbria and founded another north of the Wear; after which her history seems to become confused with that of St. Heiu and St. Begu.
In the Aberdeen breviary there is a lesson for a Saint Bega, with whom she may perhaps be identified. This St. Bega is described as an anchoret who lived in an island called Cumbria in the ocean sea, where she was sometimes visited by St. Maura. She was buried in her island, and was especially venerated at Dunbar.
[Authorities cited above.]