During the Social War (91-88BC), tensions over the matter of citizenship for Italians (and to an extent, suffrage) between Rome and the tribes of Italia rose to a civil war that was devastating for Rome. During this war, Italian allies, divided into two factions (Marsic (north) and Samnite (south)) faced off against Rome and the Latins. Although defeating the Italians, Rome granted citizenship to the tribes of Italia to prevent further violence.
However, it is clear that the Allies at its peak wanted more than just citizenship. The establishment of a new capital at Confinium (renamed 'Italica'), the establishment of a new senate modelled off the Roman senate, and the establishment of a new currency featuring iconography suggesting the Italians wanted the Roman's to be completely slaughtered shows us that the Italian leaders wished for full independence from the Roman Republic.
In OTL, this war had no clear-cut victor. What if Rome had lost and faced the same fate as Carthage, with a new, federation of tribes of Italy replacing it basing their model of government off the Roman model but with more consideration towards equal representation of tribes? What would become of the provinces of Rome?