According to the practice in Italian cinema at the time, most actors (including the Italian ones) are dubbed.
A curiosity: The celebrated Italian voice-dubber Rita Savagnone is lending her voice to two actresses (Gina Lollobrigida and Danielle Godet), which is quite unusual as they have scenes together. The result is that the spectator has the impression it is a monologue.
Same thing for Pino Colizzi who is also dubbing two actors.