Senán mac Geirrcinn was a 6th-century Irish bishop and abbot who lived in the Munster region. He is recognized as a founder of several religious sites, most notably the monastery on Scattery Island (Inis Cathaigh) in the Shannon estuary. As a significant figure in Irish tradition, he is included among the Twelve Apostles of Ireland and served as a patron for the Corco Baiscinn and the Uí Fhidgeinte. His life was marked by extensive travels across Europe, including visits to Rome, France, and Britain.