My personal favorite bit of linguistics history is that one time a guy created a language that got adopted by a cult-like-group that was trying to create a superior human race...
The full article can be read here.
It is a rather lengthy article. So TL;DR
A guy that spent his entire life working at a DMV office secretly spent his whole life also working on a conlang (an artificial language). The language is founded on the idea of being the most precise language possible, removing all ambiguities in speech. The creator pulled from hundreds of different languages and combined the different features languages use to make sense of the world around us.
A secret underground organization picks up on the idea and grammar of this language and then begin speaking it in an attempt to become proficient speakers of the language to help improve the efficiency of their brain. As well as raise their children speaking it in hopes to create a superior human race.
But it’s a fascinating article that I would highly recommend reading. It’s totally worth it because some crazy shit goes down.