The name was first recorded in a 971 charter by the King of Burgundy.
Two historic churches from the 12th and 16th centuries are located here. The architect Le Corbusier designed a group of modern buildings, called "Firminy Vert", which includes a church Saint-Pierre, Firminy, cultural center, and a residential building.
It has important coalmines known since the 14th century and extensive manufactures of iron, steel, and aluminum goods, including railway material, machinery and cannon. Fancy woolen hosiery is also manufactured.