He was born in Ireland before the middle of the sixth century. He was a monk from his youth and was learned in both sacred and secular literature. At the age of 45 he left Ireland and went to Europe, where he founded three monasteries in what is now France. His monastic rule was strict, based on Irish practice.
King Thierry II of Burgundy had a veneration for Columbanus and often visited him. Columbanus’s criticisms of Thierry’s debauched living and practice of concubinage enraged the king’s grandmother Brunhild, and eventually Columbanus and all other Irish-born monks were ordered to be deported to Ireland. They eluded their captors, and after an unsuccessful attempt to evangelize the pagan tribes near modern-day Zürich they reached Italy, where Columbanus founded the monastery at Bobbio. He died there in 615.
The Rule of St Columbanus was eventually superseded by the milder Rule of St Benedict. Columbanus’s writings are among the earliest evidence of Irish knowledge of Latin. Some of what he wrote related to ecclesiastical controversies of the time and is no longer read, but several extracts from his “Instructions” are still part of the Office of Readings. His style combines an underlying passion with a strong and rhythmic rhetorical structure.
