Senán mac Geirrcinn
Irish saint
Feast: 1 March (not on the universal Roman calendar; kept in the Roman Martyrology or local calendars)
Who they were
Senan, born near Kilrush in County Clare about 488, studied under holy abbots and founded a church near Enniscorthy about 510. He visited Menevia, Rome and Tours, and on his return founded churches on several islands.
He finally settled on Scattery Island in the Shannon, which became a famous abbey and the seat of a bishopric with him as first bishop. He was visited by Sts Ciaran and Brendan, and founded two convents for nuns. He died on 1 March 560.
The miracles
There was never a formal cause: he has been honoured as a saint since before the Church's formal processes began.
Why that counted as sanctity
A monk-bishop of the islands of the Shannon.
- Catholic Encyclopedia (1913), via New Advent - St. Senan
- Wikidata Q2480928 — dates, feast day and identifiers (CC0)
- English Wikipedia — Senán mac Geirrcinn (CC BY-SA)
Checked against the sources listed on 21 September 2026. Corrections welcome.