Although the current structure of the village dates back to the late Middle Ages, its origin is certainly much older. The first dwellings clearly date back to Roman times, as suggested by the ruins found near the church of St Mark.

The first official reference to Clauiano, however, appears on a parchment dated 13 July 1031. On that day, Poppo of Treffen, the Patriarch of Aquileia, inaugurated the reconstructed basilica and established the Chapter to which it gifted a wide territory to be maintained, including “Cleuian”, the current Clauiano.