Olcán was a 5th-century Irish saint and a follower of Saint Patrick. According to tradition, he was discovered as an infant near Armoy, where he later established a monastery and served as its bishop. After being ordained at Dunseverick Castle, he traveled to Gaul for his education before returning to Ireland. His religious community was closely associated with the Dál Riata people, and he was granted significant relics by Patrick to strengthen his mission in the northeast of County Antrim.