Azbubu
Honorary Master
If you want to rent a car, you definitely need to. And for Italy, you probably do want to rent one so you can travel the countryside there, it's really quite nice.
Like I said, I didn’t. But perhaps ymmv.
Edit: actually no, it doesn’t.
An International Driver's Permit (IDP) is also mandatory by law for non-European Union renters except for customers from the following countries who can rent with their national driver's licence and passport: Argentina, Australia, Bolivia, Brazil, Canada, Colombia, Israel, Mexico, New Zealand, South Africa and United States.