Saint Gwen Teirbron was a Breton

Breton people

The Bretons are an ethnic group located in the region of Brittany in France. They trace much of their heritage to groups of Brythonic speakers who emigrated from southwestern Great Britain in waves from the 3rd to 6th century into the Armorican peninsula, subsequently named Brittany after them.The...

 holy woman who supposedly lived in the 6th century. Her epithet is Welsh

Welsh language

Welsh is a member of the Brythonic branch of the Celtic languages spoken natively in Wales, by some along the Welsh border in England, and in Y Wladfa...

 for '(of the) three breasts'.

Veneration

Popular devotion interpreted Gwen's unusual physical and spiritual fecundity by God's gift to her of a third breast. Her iconography naïvely followed suit. Gwen is invoked for women's fertility. She is commemorated on 3 October in the Catholic Church (although this has been transferred from Saint Candidus of Rome), and on 18 July (NS

Old Style and New Style dates

Old Style and New Style are used in English language historical studies either to indicate that the start of the Julian year has been adjusted to start on 1 January even though documents written at the time use a different start of year ; or to indicate that a date conforms to the Julian...

) by the Russian Orthodox Church Abroad in Australia.

Possible identification

She is interpreted by Dyfed Lloyd Evans as having been a euhemerized mother goddess.