Chassenon is a commune in the Charente department in southwestern France.

The ancient name of the village was Cassinomagus.

Situated on the Agrippan Way (Lyon - Saintes), Cassinomagus was, in the Roman times, important enough to be mentioned on the mediaeval Peutinger map as one of the two secondary towns between Limoges and Saintes. The remains of this Gallo-Roman town lay on about 300 hectares and include a sanctuary of about 25 hectares. This sanctuary consisted of several monuments: a big temple, two small ones, a theatre (amphitheatre ?), and thermal baths. The baths, which are very well preserved, can be visited.