Perhaps this is the origin of this Roman capital installed in the first century BC at the foot of the mountains of Diois.

It shared with Vaison-la-Romaine the title of chief city of Vocontii, an important romanized Gallic people.

Little by little, the city withered, eventually becoming a mansio, merely a station on the side of a Roman road, by the beginning of 4th century.

A fort was however installed at the same time at the top of the peak of Luc, in order to supervise the road, which acquired a strategic importance since the Roman armies fought on the Rhine.

The road, which ran between the Durance and the Rhône, was the most practicable route in winter to connect Milan and Cologne.