To fully understand the current linguistic situation in Italy we need to take a look at the history of the nation. At the time of the unification of Italy in 1871, there was no one language spoken throughout the country; instead, there were as many languages as there were villages! These languages, the Italian dialects, all came from different varieties of spoken Latin, and although they shared many common elements, they were not all mutually intelligible. Some, such as the Sicilian dialects, had incorporated influence from the language of the Greeks who had occupied their land, while others in the North had been affected by the Celtic languages previously spoken in their regions before the invasion of the Romans and the spread of Latin. These, along with other factors, led to many different versions of Latin being spoken in the different regions, which have evolved today into the many contemporary Italian dialects.
However, a nation doesn’t really work if people from different regions are unable understand each other, or more importantly the language of the rulers. So after the unification of Italy one of these dialects was chosen over the others to become what is now known as standard Italian. The language chosen for this was the literary Tuscan dialect, the language of Dante and Manzoni, and it was spread through the country with the help of the TV.
For a while, dialect use, although often continued at home, was discouraged in public as it was seen as the language of the uneducated, and during Mussolini’s dictatorship its public use was outlawed. Fewer and fewer people spoke their regional dialects and some wondered whether they would die out in favour of the potentially more useful standard Italian. However, with the rise of bilingualism (Italian and dialect), its prejudice is reducing, and it is more often seen positively, as an additional expressive tool. Now, bilingual Italians can choose which language to use, and while standard Italian is still becoming more common for general communication, when Italians are angry, or want to express emotions, a sense of belonging or shared experience, they often turn to dialect to allow them to express what standard Italian cannot.
*these figures are debated, depending on which territories you count, and what counts as a different language.