The Puy de Dôme is an extinct volcano located pretty much smack in the middle of France. It last erupted some seven thousand years ago, which in geological terms is fairly recent - prehistoric humans might even have born witness to that eruption! What I'm wondering, though, is what drove this volcano, seeing as it is not located where tectonic plates meet? Was there a hot spot underneath central France that powered this volcano, and if so, could we witness future volcanic activity in this region?
According the an Oregon State website,
Volcanism far from the edges of tectonic plates, such as Chaine des Puys, is rare. Changes in the mantle may have led to volcanism at Chaine des Puys. Several lines of evidence indicate thinning of the crust and upwelling of the asthenosphere. The rising mantle "diapir" was probably a total of 30-60 miles (50-100 km) in diameter.
Chain des Puys is the 40km long chain of volcanic features to which Puy de Dome belongs. It sounds like the causes are not completely understood. Unfortunately, all the papers I could find on the topic are in French (understandably), so if you can read French you can try Google Scholar to see if there is more info there.