Born in Templemartin, near Bandon, and originally named Lóchán (modern form, Loan), he was the son of Amergin of Maigh Seóla. He studied in Ossory, corresponding approximately to the present County Kilkenny. He was renamed “Fionnbarra” (Fairhead in Irish), reportedly when, on being tonsured, the presiding cleric remarked: “Is fionn barr (find barr, in the Irish of the time) Lócháin”, meaning, “Fair is the crest of Loan”), and he then became known as “Findbarr” (“Fionnbarra” in modern Irish)
On completion of his education he returned home and lived for some time on an island in the small lake then called Loch Irce. The island is now called Gougane Barra (the little rock-fissure of Finnbarr). He is reputed to have built small churches in various other places, including one in Ballineadig, County Cork, called Cell na Cluaine, anglicized as Cellnaclona and sometimes referred to as Cloyne, causing it to be confused with Cloyne (Cluain Uamha) in east Cork. It was in Cell na Cluaine that, years later, he happened to die.
He settled for about the last seventeen years of his life in the area then known as “an Corcach Mór” (Great Marsh), now the city of Cork, where he gathered around him monks and students. This became an important centre of learning, giving rise to the phrase “Ionad Bairre Sgoil na Mumhan” (“Where Finbarr taught let Munster learn”), chosen for motto by today’s University College Cork.
His church and monastery were on a limestone cliff above the River Lee, an area now known as Gill Abbey, after a 12th-century Bishop of Cork, Giolla Aedha Ó Muidhin. It continued to be the site of the cathedral of his diocese. The present building on the site, owned by the Church of Ireland, is called Saint Fin Barre’s Cathedral. The people of Cork often refer to it as the South Cathedral, distinguishing it from the North Cathedral, the Catholic Cathedral of Saint Mary and Saint Anne.
Finnbarr died at Cell na Cluaine, while returning from a visit to Gougane Barra. He was buried in the cemetery attached to his church in Cork