Just like for the gallo-roman period, the museum has an important stonework collection for the medieval period.
When the Western Roman Empire fell down in 476, Die was still an important city. Indeed, in 325 the first bishop of the city, Nicasius was the only representative of the Gauls at the Council of Nicaea.
From the Carolingian period onwards the city is administrated by a count but, while this office becomes hereditary, the last one ruines during the crusades. From then on the bishop recovers the count’s powers.
In 1441 the Pic of Luc is victim of a landslide. The road leading to the Alps is then blocked by two lakes formed this way. This is the dawn of a very important economic crisis for the entire region.
In 1450 the Diois enters the Dauphiné province, governed for a houndred years by the eldest son of the king of France. Thus the Diois enters the kingdom of France only in the 15th century, whereas it had until then depended on the Holy Roman Empire and the Count of Toulouse.
At the time of Reformation, eighty percent of Die inhabitants becomes protestant. The city convents even vote for the change of doctrine by a majority.