During the mass emigration from Italy during the century between 1876 to 1976, the U.S. was the largest single recipient of Italian immigrants in the world. However, their impact was not as great as countries like Argentina and Brazil. That was due to the fact that hundreds of thousands of immigrants from nations all over the world were migrating to the U.S. at the same time and American born natives already made up the majority ethnic group. The Italians did play a major role though, socially with individuals rising to national stature in many different fields.
The name Italia, probably a Graecized form of Italic Vitelia (='calf land'), was originally restricted to the southern half of the 'toe' but was gradually extended. By 450 B.C. It meant the region subsequently inhabited by the Bruttii; by 400 it embraced Lucania as well. Campania was included after 325, and by Phyrhus' day Italia as a geographical expression meant everything south of Liguria and Cisalpine Gaul; this area however only acquired political unity after the Social War. Cisalpine Gaul was not officially incorporated until Augustus' time when, accordingly, Italy reached its natural Alpine frontiers. Unofficially, however, whatever the administrative divisions, the whole country south of the Alps has been called Italy from Polybius' time onwards. ...
As a nation state, Italy has emerged only in 1871. Until then the country was politically divided into a large number of independant cities, provinces and islands. The currently available evidences point out to a dominant Etruscan, Greek and Roman cultural influence on today's Italians.
The earliest human settlements within the territory of present-day Italy date almost certainly to the initial phase of the Quaternary era (Pleistocene). This period was characterized by frequent alternation in climatic conditions, with consequent phases of expansion and retreat in the Alpine and Apennine glaciers and relative variations in sea level.