The career of Italian and Dante's role, in brief (Updated)

[Note: A much better map of Italian dialects has been supplied by our friend Peter D'Epiro (thanks Pete!). A few minor changes to the text as well.]

Back when we were reading Ovid, we looked briefly at the amazing variety of tongues in pre-Roman Italy (6th century BC), and noted that Latin was one of the smallest linguistic regions of the peninsula, as shown in this image:

Pre-Roman languages of Italy

Long after Latin became the dominant tongue, it broke into the Romance Languages, and within Italy into many dialects. The complex and "completely chaotic" story of Italian linguistics is shaped by the political history of Italy as well as by its geography.

Here's a political map before Italy was united:

Pre-Unification Italy

Dan Nosowitz offers an amusing overview of Italian's trajectory in a story from Atlas Obscura:

“One thing that I need to tell you, because this is something that is not clear even for linguists, let alone the layperson—the linguistic situation in Italy is quite complicated,” says Mariapaola D'Imperio, a professor in the linguistics department at Aix-Marseille University who was born in Naples and studied in Ohio before moving to France. The situation is so complicated that the terms used to describe pockets of language are not widely agreed upon; some use “language,” some use “dialect,” some use “accent,” and some use “variation.” Linguists like to argue about the terminology of this kind of thing.

The resulting mescolanza of dialects is shown in this map of dialects, some quite exotic sounding:*

A key role in the fashioning of more or less "Standard" Italian was played by our poet:

During unification, the northern Italian powers decided that having a country that speaks about a dozen different languages would pose a bit of a challenge to their efforts, so they picked one and called it “Standard Italian” and made everyone learn it. The one that they picked was Tuscan, and they probably picked it because it was the language of Dante, the most famous Italian writer. 

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