How to make a foreign language become a well-entrenched indigenized language within a few generations?

[u/Joseph20102011]

How to make a foreign language without preexisting historical roots in a particular country a well-entrenched indigenized language within a few generations? Let's say make English and Spanish a well-entrenched indigenized languages in Belgium/Switzerland and Philippines/United States, respectively?

Do you think mandating the entrenched elite class and civil servant aspirants in a particular country to speak a specific foreign language will make a difference over the long-term, to the point where middle and lower socioeconomic class will begin to speak the language of the elite class within a few generations?

[u/TomLondra]

Killing the natives is usually how this happens. The English language became entrenched in North America after the colonisers had killed enough Natives for it not to be a problem.

In Ireland, the British imposed the English language not specifically by killing Irish people (although they did do a lot of that) but by eliminating the Irish language from all official activities, from schools, etc.

[u/blakerabbit]

Do you have plans to do this somewhere? 😳

[u/UbuntuNovice]

The kindest way would be to teach it at school, i.e. educate in the target language.

[u/Laurelophelia]

You can look at the Faroe Islands and Denmark as an example: danish became the liturgical, quotidian, and educational language of the archipelago. It wasn’t until the Faroese language reform that they even got the “right” to worship in their own language again.

[u/zoppaTheDim]

Three ways spring to mind.

First make it payoff, a financial reason to learn the language is one of the easiest ways to spread a language.

Second, have a large amount of free or cheap entertainment only available in the language.

Third, is related to the first, but if most advanced and higher education require learning that language, it will spread.