The origin of Bagnols, according to the etymology of its name (from the Latin word balnéarius: place where we have baths) goes back to Roman times.

The City’s coat of arms represents moreover three golden washbasins to which were joined, later, the three fleurs-de-lis of the Bourbons, Lords of Bagnols

In the records of the City’s striking historic facts is the 4th century construction of a sanctuary where the church is currently located. During the next centuries, Bagnols experienced the development of religious movements and with them the construction of chapels, such as Saint-Pierre-de-Castres

In 1208, the first municipal charter was signed and contributed widely to the expansion of the City just as the market created in 1223. The 14th century saw Bagnols being equipped with fortifications to protect itself from looters and from rebel farmers, known as the "Tuchins". The religious wars, the Reform and by 1580 grave epidemics of the plague followed. In spite of these painful events,

Bagnols continued to prosper, and in the 17th century, the silk industry set up there for 300 years of prosperity.

At this point, a memorable episode in the history of the City arose. In 1631, the Duke of Montmorency, Governor of Languedoc and Lord of Bagnols revolted against Louis XIII. He was beaten, condemned and executed. In retaliation, the King ordered the demolition of the City’s castle and walls, later reconstructed in the 18th century in order to defend the town from possible assaults by the Camisards.

The city continued to develop in the 19th century and grew beyond its initial space with the creation of Mont Cotton (1843) and the Lacombe Boulevard (1874). Bagnols, with the addition of "sur Cèze" at the request of the Post and Telegraph offices in 1891, has maintained its charm and protected the traces of its rich past.

Currently Bagnols-sur-Cèze is home to approximately 18,000 inhabitants; its expansion is owed notably to the creation of the Marcoule reprocessing and nuclear research site just a few kilometers to the south of the city.