Which countries keep their native languages pure and uninfluenced from foreign languages?

What Tomasz Dec’s answer to Which countries keep their native languages pure and uninfluenced from foreign languages? said. Icelandic is likely the most successful, as the poster-child of conservative intervention in language change in general. Lots of European languages have had bouts of this. German fought the good fight for a fair while, and their vocabulary is more purist than many on the continent, but it wasn’t as thorough going as some. Greek quite successfully eradicated or marginalised Italian and Turkish from their vocabulary, and came up with lots of native coinings for terminology—before they gave up and let French in. Turkish had a major campaign of eradicating Arabic and Persian words for made up  Turkic words—and French.

Noone’s said much about non-European languages. There are loans in Chinese alright, but in a (largely) monosyllabic language like Chinese, mass influx of Latin or English terminology is not as practical. There certainly has been mass influx of English into Japanese, though their phonology makes the loans look quite different.

Should countries do it? It’s a matter of their ideology and their feeling of insecurity in the world. I won’t say they have to.

I also won’t say they needn’t bother, or make fun of them for doing so. Two groups do:

1. Linguists, but this is not a linguistic issue, it’s a sociolinguistics (and indeed primarily sociological) issue, so it’s none of their business. It’s not the communicative adequacy of a hybridised language that’s at issue, it’s whether the community want to have a hybridised language.
2. English speakers: “Ooh, look at us! We don’t have an Academie, like those awful Frenchies! Our language is a mongrel, so that makes it superior to any language spoken in history, aren’t we special.” No, no, you’re not, pilgrim. Your societies just happened to have made a different choice in the 16th through 19th centuries. And had a choice imposed on them in the 11th through 15th century. That doesn’t make you special, just different.