He was a member of the Cinel Domaingen, a branch of the
Sogain of
Connacht. He studied at the monastic school of
Clonard in
County Meath, where he became associated with Saint
Finnian of Clonard. About 550, after completing his education, he founded a
monastery on the east bank of the
River Suck, at a wood (
ros) which was called after him (
Ros Comain). Ros Comain was situated on Magh nAi (later known as
the plains of Roscommon/
the plains of Boyle), homeland of the
Ui Briuin Kings of Connacht. He successfully sought their patronage, ensuring his influence within their spheres of power. His successors are named in the
Irish annals between the years 782 and 1135. He has been linked with the foundation of Kilcommon in
County Mayo and the early monastic church at Leithglin,
County Carlow. He composed a rule for monks, which came to be observed by many religious bodies in Connacht. His
feast day is 26 December. == See also ==