The island, known to the Romans as Lerina, was uninhabited until Saint Honoratus founded a monastery on it at some time around the year 410. According to tradition, Honoratus made his home on the island intending to live as a hermit, but found himself joined by disciples (including Saint Caprais (Caprasius) who formed a monastic community around him. This had become “an immense monastery” by 427, according to the contemporary writings of John Cassian.
The monastery provided three bishops for the See of Arles: Honoratus himself, followed by Hilarius and Cesarius in the fifth and sixth centuries, respectively. Reputedly, Saint Patrick, patron of Ireland, studied at the monastery in the fifth century