Historische Verbreitung der Regionalsprachen Frankreichs

Pretty sure Corse has a regional language my dude.

Yeah no, I’m Switzerland we have a “different” language that french don’t use and mostly don’t understand
Like french would say “quatre-vingt” we say “huitante”
And even in Switzerland just by the word you use for different thing we can tell where you’re from (the national press made a game(?) where you can see where you from just by the word you use
It works quite well

Shouldn’t the Ile de de france dialect be francilien or are you trying to depict ancient historical dialects?

The border Gallo / Angevin is super Wrong. Gallo should reach south up to the Loire and there is a transition zone with the poitevin saintongeais, while Angevin is limited to the border between Loire-Atlantique and Ille-et-Vinaine to the East and touches Normand and Tourangeau.

You also miss the Francique spoken next to Alsatian, West Vlaams spoken in the extreme North in particular the Frans Vlaams dialect, and down south, I don’t know why Catalan stops at the border while your Basque crosses it.

Finally poitevin-saintongeais is one group (polycentric language).