The national language of Italy and one of the four national languages of Switzerland (where it is spoken in the canton of Ticino); also spoken by some bordering communities in Slovenia, Croatia and France.
Italian - or rather the many widely varying dialects of the Italian peninsula - evolved out of Latin following the collapse of the Western Roman Empire, influenced by the languages of the invading tribes from the north, not least the Lombards. By comparison with the other romance languages it has retained more of Latin's fluid word order, but like them it has lost its case inflections and relies more on compound verbal tenses.
As the spoken language changed, Latin continued to be used for writing. The earliest written evidence of an Italian vernacular comes from 10th century legal documents quoting illiterate witnesses to a dispute over land ownership near Monte Cassino, beginning with the much-quoted words "Sao ke kelle terre per kelle fini que ki contene, trenta anni le possette parte sancti benedicti." ("I know that these lands within these borders have been held for thirty years by the party of St Benedict..."). A couple of centuries later Dante Alighieri was the first notable literary figure to use a form of the vernacular in the Divine Comedy, not long after he had written (in Latin) a study of the languages of the peninsula, De volgare eloquentia.
The language used by Dante and Petrarch and Boccaccio in the following century set a standard for literary Italian that, more or less, lasted five hundred years, naturally becoming somewhat distant from anything actually spoken (although there was also some literary activity in the major dialects, particularly in the theatre); the influence of the Church and its status as a lingua franca meant that Latin continued to be used in many circles - for most learned writing, up to the 17th century - while the political division of the peninsula into a dozen often warring states prevented any other standard form developing. It was thus not until the Risorgimento and the unification of the Italian state in the 19th century that any serious moves were made to update the ossified literary language and unify the vast range of dialects. This task fell to a mediocre (but subsequently renowned) novelist, Alessandro Manzoni, whose I promessi sposi was the first work in the modern Italian language which he invented, taking as his base the dialects of Tuscany and Florence in particular; Tuscany, having been home to Dante, Petrarch and Boccaccio, was held to be the home of the "purest" dialects. Nonetheless certain aspects of Tuscan dialects as they had evolved ran against usages which were common across large swathes of the rest of the country, so the new creation was not just Florentine writ large.
The newly unified state made substantial efforts to impose the new standard language through the education and legal systems, with a further contribution being made through mass military service in the age of conscript armies. During the Fascist ventennio, further attempts were made to purge the language of foreign influences (which is why the Italian for football is calcio (literally "kicking") rather than a localised form of the English word as it is almost everywhere else on the planet.) During this period the educated part of the population was effectively bilingual; the vast majority of communication, even in quite formal contexts, was still in regional dialects, which did not bear the social stigma they tend to in English, indeed, rather the reverse in some places. It was not until the advent of the mass media, and the rise of first Cinecittà and then television in the years of the post-war economic miracle, that speaking in lingua started to become the norm; a majority of Italians still spoke in dialect for preference until the 1970s, and plenty still do.