The patron saint of Castel di Lucio is Saint Placidus, celebrated on 5 October.
The town was settled in the Norman period by families from continental Italy and southern France, and its original name, «Castelluzzo», came from the small castle that stood on the rock. It was subject first to Enrico II Ventimiglia, as part of the county of Geraci in the second half of the 13th century, then to his nephew and successor Francesco I Ventimiglia, at least from 1311, by which time it must already have grown into a village gathered around the fortress. The name Castelluzzo first appears in a document from 1271, when Charles I of Anjou assigned it to Giovanni di Montfort, and again in 1283, on the occasion of the levy imposed by Peter of Aragon upon his arrival in Sicily after the Sicilian Vespers: on that occasion, Castelluzzo contributed six archers to the royal army. The Ventimiglia castle, built in the 12th century, dominates the Tusa river valley from over 350 metres, with the remains of a bastioned wall still visible to the south-west.
