[1] According to Leland's text, Breage was born in the region of Lagonia and Ultonia in Ireland, an unclear description perhaps referring to Leinster and Ulster.
She became a nun at an oratory founded by Saint Brigid of Kildare at Campus Breace (the Plain of Breague; modern Mag Breg in County Meath).
Around 460, she travelled to Cornwall with a company of seven other Irish saints: Germoe, Senanus (Sithney), Mavuanus (perhaps Mawnan), Elwen, Crowan, Helena, and Tecla.
They settled at Revyer on the River Hayle, but some were killed by the local ruler Tewdwr Mawr of Penwith, a tyrant appearing regularly in Cornish hagiographical works.
[3] Undeterred, Breage travelled through Cornwall, visiting the hill of Pencaire and establishing a church at Trenewith or Chynoweth.
In the 19th century, residents of St Levan held that Breage was the sister of the town's saint Selevan or Salaman.
The hagiography is replete with stock elements: her association with other locally venerated saints as companions, her conflict with a heathen tyrant, and her establishment as a hermit in a remote part of the parish that was later named for her.