Originally, Louis de Funès only considered a TV adaptation of Molière's play. Encouraged by the actor's enormous popularity however, the producers took the risk to bring it to the big screen. Sadly enough, "L'Avare" ended up much being much less successful than de Funès' pictures usually were.
In the scene with Harpagon and Master Jacques, the horses in the background were drawn by Albert Uderzo, the creator of 'Asterix'.