St Ciarán of Clonmacnoise (September 9) founded a monastery attracting recruits from all over Europe

Ciarán (c 515-c 545) was the founder of Clonmacnoise monastery, sited by the river Shannon on a ridge of sand and gravel deposited by a glacier in the muddy middle of Ireland.

The land had been given to Ciarán by Diarmaid mac Cerbaill, the first Christian to be acknowledged as High King of Ireland. Nothing remains of the original wooden buildings. Ciarán, in fact, died of the plague when the tiny community was only a few months old.

His monastery, however, flourished, notwithstanding frequent attacks over the succeeding centuries by Irish, Viking and Anglo-Norman marauders.

Apparently the monks of Clonmacnoise could hand out punishment as well as take it. In 764 they engaged in a pitched battle with their rivals at Durrow Abbey (founded by St Columba), slaughtering some 200 of them.

By the ninth century Clonmacnoise, now built in stone, had become the most celebrated monastery in Ireland, attracting recruits from all over Europe on account of its reputation for learning, and for craftsmanship in stone and metals.

Still surviving is the the high-standing ninth-century Cross of the Scriptures, decorated on all four sides with sculptures representing the Passion, the Last Judgment, and Christ with St Peter and St Paul – along with a depiction of King Diarmaid and St Ciarán performing their good work.

The Clonmacnoise Crozier (c 1100), decorated in bronze and silver, is now in the National Museum in Ireland, while the monastery’s 12th-century Book of the Dun Cow, recording various legends, is one of the oldest surviving manuscripts written in Irish. 

In the 11th century there were some 1,500 souls at Clonmacnoise. Yet after 1150 the monastery fell into decline as the Church in Ireland adopted a diocesan rather than a monastic framework.

New religious orders arrived from the continent, while the development of Athlone, to the north, drew away trade. Clonmacnoise gradually became a collection of ruins.

Ciarán, however, remained an Irish hero. A chariot-builder’s son, he had studied under St Finnian at Clonard, and then with St Enda on Aran. There, he had a vision of a huge tree stretching out all over Ireland. Enda was not slow to interpret: “You are the tree and all Ireland shall be filled with your name and sheltered by the grace within you.”

As he lay dying, Ciarán instructed his monks: “Let my relics bleach in the sun like the bones of a deer; better for you to dwell in heaven for me, than at home with my relics.”

When Pope John Paul II visited Clonmacnoise in 1979 he declared that the ruins were charged with a great mission. Certainly Ciarán’s work is not yet done. Since 2007 there has been a Catholic summer festival for the young alongside the remains of his monastery.