French regions are purely administrative without historical weight except a few exceptions. Even Britanny doesn't have its historical capital city in Britanny for rational economical reason.
France is a centralised country. Even the départements which are relatively recent (just before, during and after the evolution with napoleon) were born of necessity. The idea was just to delimit a district which would cover at least half a day for walking territory and at best 1 full day.
So out with religious or cultural sensitivities, provinces were meant to be broken down in a rational way.
Regions are just the same. Especially now that the 24 been merged into 12.
Occitania my region roughly covers the historical Duchy of Toulouse. Honestly I don't feel attached to Toulouse as much as I was to Montpellier, the capital of the former region of Languedoc-Roussillon.
The flag is just a mix of a cross of the "midi" and the Catalan stripes so they wouldn't be too grudgy like the bunch of rugby playing mountain dwarves they are (lived amongst them).
Fichier:Flag_of_Région_Occitanie_Perpinyà_variation.svg Occitania
The cross of Camargue: super popular unofficial icon of the historical region where I reside
https://www.drapeaux-flags.com/images/drapeaux/500px_norm/CROIXCAMARGUE.png