Before the Social War, "Italians" were those living in Italia who did not possess full Roman citizenship. Each group had its own particular set of rights and privileges in the Roman system, usually going back decades or centuries to the time when Rome had defeated or otherwise brought them into her sphere of influence. Virtually all of them spoke Italic languages (the branch to which Latin belonged) or else Greek, or both, and many were also dual native Latin speakers, and most of them had societal and cultural parallels with the Romans.

Some "Italians" had been close Roman allies for centuries, like the city of Venusia, in central southern Italia. She was captured in 291 BCE after the Third Samnite War and was granted colonia status. She remained loyal during Hannibal's extended ravages in Italy, and her rebellion in 91 was a major symbolic blow.

The major elements of the "Italians" at the time of the Social War were (in no particular order): the people of Etruria; the Samnites; the people of Umbria; the old Greek cities of Campania (including Capua, Pompeii, and Nola); the Marsians; the people of Picenium; the Paeligni/Vestini/Marrucini; the Lucanians; and the Hirpini. All of these, through various ancient or more recent treaties, were required to provide Rome with soldiers in her wars, but were given an unequal "share" of the proceeds from those wars. They were nominally free to administer their own local business, but Rome controlled their foreign policy, in particular their relations with each other. This prevented them from associating with one another and discouraged the formation of "leagues" or federations which might present an organized bloc against the Roman status quo.