With all the focus in Southern Italian history being on exotic influences (which as we've posted before make up a very small part of the Italian genome), people often forget that there were people in Italy, in great numbers, who were highly civilized, before the peninsula was Romanized, and aside from the [insert invasion name here].
One of the most influential civilizations in Italy was that of the Samnites (Italian: Sanniti), a group of Oscan-speaking tribes, sometimes called "Sabellian," who lived in the interior of Italy. If you are Italian and come from any region from Rome southward (including eastern Sicily), chances are that you are of predominantly Sabellian stock. For hundreds of years, these hardy southern Italics fought off Roman domination and Greek colonization.
For a while it was even unclear who would be the master of Italy: the Romans or Samnites. After the battle of the Caudine Forks (Samnite victory over Rome, 321 BC) and right before the battle of the Colline Gate (Roman victory over Samnites, 82 BC), it looked like the Samnites would be the masters of Italy (and perhaps an empire).
Archaeologists recently discovered an intact Samnite tomb, dating from 2400 years ago. This was at the peak of Samnite ascendancy.
Let us hope they extract DNA. We will confidently predict here that the DNA will be related to living people in Campania (incl Naples), Molise (the heart of Ancient Samnium), Basilicata, and Calabria (especially Cosenza province).
Here is the story if you want to read it.