Remnant isn't Earth. But it is undeniable that real Earth cultures and languages inspired it.
Take Raven Branwen: Japanese inspired outfit and sword (I think? Correct me if I'm wrong), Welsh surname, and allusion based on one of the Norse god Odin's ravens, who flew around spying for him.
Or my fav, Yang Xiao Long, whose name is Chinese, but not pronounced like it would be in actual Chinese (and Yang is her first name, not her surname like it would be if arranged in the same way as Chinese names, surname first).
I've been thinking about Remnant compared to Earth for a while, long enough for a headcanon to come up in a fic I started writing in October 2023 (I've been active in RWBY fandom since September 2023, after lurking since the Bees kissed and brought RWBY to my attention).
That headcanon: Remnant has different languages, mostly according to each kingdom, but with some variations. Here's my thoughts:
Valean is the common tongue, due to the crucial role of the last king of Vale in bringing about peace after the Great War, about 80 years before the events of RWBY. Yang and Ruby are native Valean speakers, being raised on the island of Patch within the kingdom of Vale. They can probably speak a bit of Qrow's mother tongue too, a variant of Mistrali (see below).
Vacuan is the language of Vacuo, and has many different dialects due to all of the mostly nomadic tribes. Sun and Fox speak different dialects because of this, coming from different Vacuan tribes.
Atlesian is the renamed language of the kingdom of Atlas, formerly Mantlean. It's Weiss's first language, but she's also fluent in Valean, and almost everyone in Solitas (the continent where Atlas and Mantle are) can speak Valean as the common tongue. They probably pride themselves on this, but the same goes for other kingdoms too because Valean is a useful second language for trade and diplomacy.
Mistrali is the official language of the kingdom of Mistral and Anima (the continent where Mistral is) as a whole, apart from Argus, which has an Atlesian military base protecting it, and also some Atlesian citizens, so that's also an official language there. But most people speak Valean to keep things simple, especially when it comes to talking to travellers.
Settlements founded by people who didn't want to live in Mistral speak a dialect they refuse to call Mistrali, but can be understood as such. The Branwen tribe speak one of these dialects, but also Valean - bandits want to be understood when they threaten their victims, and those victims aren't always citizens of Mistral or natives of Anima.
Menagerie lacks an official language because its citizens come from all over Remnant, and a fusion language of all of them is developing naturally over time. Blake also speaks Valean, but stray words from other languages sometimes slip in, and she can speak Mistrali and Atlesian, if not as well as native speakers.
If faunus win their fight for rights in Remnant, perhaps this fusion language from Menagerie will be the new common tongue, replacing Valean. If that happens one of the last problems will be coming up with a name for it, I haven't come up with one: names are tricky.
