Mac Feorais was a member of the de Bermingham family, Baron Athenry.
Mac Feorais was the Gaelic form of their surname, and by Archbishop's lifetime, had become deeply Gaelicised.
He was possibly a younger brother of Walter de Bermingham, Lord Athenry, who died 1428.
The History of the Popes has no information on him, instead quoting from the Annals of the Four Masters: "The Archbishop of Connaught (Tuam), of the Bermingham family, died."
This article about an Irish Catholic bishop or archbishop is a stub.