According to the 1991 census, Italy had a population of 56,778,031. The 2001 estimated population is 57,679,825, giving the country an average population density of 191 persons per sq km (about 496 per sq mi).

Italians cannot be typified by any one physical characteristic, a fact that may be explained by the past domination of parts of the peninsula by different peoples. The Etruscans in Tuscany and Umbria and the Greeks in the south preceded the Romans, who “Latinized” the whole country and maintained unity until the 5th century. Jews arrived in Italy during the Roman Republic, remaining until the present day. With the collapse of the Roman Empire in the West, Italy suffered invasions and colonization, which inevitably affected its ethnic composition. With some exceptions, the north was penetrated by Germanic tribes crossing the Alps, while the south was colonized by Mediterranean peoples arriving by sea. The Byzantines were dominant in the south for five centuries, coinciding with the supremacy of the Lombards (a Germanic tribe) in Benevento and other parts of the mainland. In the 9th century Sicily was invaded by the Saracens, who remained until the Norman invasion in the early 11th century. The Normans were succeeded by the Aragonese in 1282; in 1720 Sicily came under Austrian rule