Under the Roman empire, Pézenas (Piscenae) developed because of its geographical position on the Roman "routes".
In 1261, Pézenas became a Royal Seigniory; her trade fairs (3x per year) took on importance.
At the time of the Albigensian crusade, the city became the property of Simon de Monfort and was then passed on to Saint-Louis.
In the middle of the 15th century, Pézenas became the center for gathering of the Etats Generaux of the Languedoc region.
Pézenas was at the peak of her strength in the 17th century until Richelieu reacted against the revolt and destroyed the castle.

Between 1650 and 1657, Molière stayed with his theatrical company and performed for the Prince of Conti. He went almost daily to the barber shop belonging to his friend Gely, where he drew inspiration for theatrical characters by observing the townspeople. He left Pézenas for Paris when he lost the patronage of the prince.
In the 17th century, thanks to the revival of its trade fairs, which had known their hour of glory in the Middle-ages, Pézenas played an economic role beyond the city itself.
The advent of the railway in the 19th century made its mark without Pézenas. Despite the demands made by the city, the authorities of the time decided on a coastal railway system. In consequence, the city’s economic activities declined, and Pézenas lost much of its influence. This result, on the other hand, has allowed the city to preserve its heritage.