I think you would need a whole year of museum visiting just to have a glimpse of all pre-Roman civilizations in Italy. The Museo Sannitico in Campobasso (https://www.musei.molise.beniculturali.it/musei?mid=208&nome...) is one among them.

Everyone forgets about the Samnites, who required Rome to fight 70 years before getting rid of them!

In high school we did a two week tour of Italy. I can really recommend it to everyone. My uncle has taken my nieces for holidays all over Italy for 16 years to show all the nice places and art.

Thirded - Like many of the less-touristy museums in Rome, it's a museum for grown-ups. I think the average HN'er would appreciate it :)

Fourthed - it's also a gorgeous museum, in that it's covered with beautiful Etruscan frescoes, and the grounds feel more ancient and down to earth without pandering. And it's pretty hard to find Etruscan artifacts, so it's a one-stop-shop.