the fight for universal public education was a long one and wasn't won in France until roughly a century after the Revolution when Jules Ferry drove it. Financing was (and is) always an issue in what was (and is) a bourgeois republic. At the time of Daudet's story (Daudet being, and I don't know if you intended the irony, an Occitan speaker and writer) probably half of all the french soldiers fighting the Prussians were illiterate.

Suffice to say that I doubt very much any Occitan, Provençal or Breton public school students woke up one day to learn they were no longer going to be taught in Occitan, Provençal or Breton, but instead were going to be instructed in the French language. Why? Because there was no such thing as an Occitan, Provençal or Breton public school.

The Hun is always either at your throat or at your feet. Winston Churchill