system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why did French suppress other languages like Occitan to become the national language?
gpt
This is somehow "normal" when it comes to nation building. Many countries as we know them today had to push their national language from varieties spoken in the capital city, which was usually considered the educated language of the elites. If they hadn't done this, maybe that country wouldn't have become a single entity as they exist today.

The Iberian peninsula has Romance varieties like Catalan/Valencian, Castillian (modern Spanish), and Galician/Portuguese, and Basque, a language that is not Romance, but in its own family. From there two countries were born, Spain and Portugal. At some point in history they were a single country. If history had played differently, today the entire peninsula could have been a single country, and maybe Portuguese would be a regional language like Catalan is today. Instead, currently we have two countries, and some Catalans and Basques want to create their own countries.

Italian has many varieties as well, Venetian, Florentininan, Sardinian, Sicilian, etc. They eventually settled in the varieties surrounding Rome and Florence as a standard Italian.

The German world has very heavy dialects in the South, Bavaria and Baden-Württemberg, but also Austria and Switzerland, while in the north there are dialects in Niedersachsen and Nordrhein-Westfallen that are closer to Dutch. When the Prussians became the principal German kingdom, they basically created the Standard German by pushing their Berlinesse-Brandenburg dialect.

If you don't define a national language, you have fractures, like the process of Balkanization that occured in the Balkans, where Serbians, Croatians, Montenegrins, Bosnians, etc., basically speak the same language but with small differences and regionalisms. They consider their languages to be different, although most linguists classify them as just being varieties of the same language. Yugoslavia was supposed to be that single country, but it didn't work, and it just broke up.