Saint Columbanus (born, West Leinster, Ireland, in 543; died at Bobbio, Italy, November 21, 615), Irish missionary and monastic founder who came to the European continent around A.D. 590. Columbanus founded several monasteries in the Frankish kingdom, most notably Luxeuil in 590, spreading among the Franks a Celtic monastic rule and Celtic penitential practices for those repenting of sins. The practice of private confession to a priest was emphasized in this practice, followed by penances levied by the priest in reparation for the sin.
Because of political difficulties with bishops and Merovingian kings, including difficulties over the date for the celebration of Easter, Columbanus moved south into Italy in about 612, where, with the help of the Lombard King Agilulf and Queen Theodelinda, he established his final and most important monastery at Bobbio (part model for the great monastery in Umberto Eco's novel The Name of the Rose). Bobbio is between Milan and Genoa.
He is often confused with Saint Columba.