There are over 6,500 living languages in the world today, from Mandarin Chinese (730 million+ native speakers) to Xipaya (3 native speakers), with about half the world’s population being multilingual. This immediately creates a challenge for humans navigating the world, as we inevitably come face to face with people who don’t share our language.
For about as long as humans have been traveling and trading and exploring, we have been tackling this challenge in a number of ways. We create trade languages, use pictures and gestures, create dictionaries, or throw technology at the problem (with varying degrees of success). If you’re writing a fantasy world, thinking about your language landscape is both an excellent vehicle for world-building, and a rich vein of comedy and conflict.
As always, I recommend starting with research. Obviously, constructed worlds require ‘research’ that mostly takes place within one’s imagination, but the real world is a great source of inspiration to get you started. Think about how the languages in your world are related, about how people move and trade, about how and when writing might have developed. Think about naming conventions, so that people and locations from different linguistic regions have coherent naming schemes (or a concrete reason why they don’t). And then think about the interplay between language and cultural philosophy.
It’s also up to you how to present multilingual conversations. There really isn’t a right or wrong answer, as long as your audience can follow the plot. Depending on your story structure, you may employ more than one of these approaches.
One option is to follow the point of view character, and refrain from translating words or sentences which they do not understand. For example:
Jennifer held out her map to the woman. “Am I close to Tasiilaq?”
The woman stepped away. “Tuluttut oqalutangilanga,” she said.
You can choose whether or not to italicize– although this is convention, there’s also some strong arguments against the practice.
Another is to telegraph language shifts in your dialogue tags. For example:
“I’m not sure about this,” Hanako said. She leaned towards Kenji, and switched back to Japanese. “I don’t trust him at all.”
If both your characters are speaking in a language other than the language in which you are writing (such as the Igbo speakers in Half of a Yellow Sun), you can render their dialogue predominantly in the language in which you are writing, but retain words which describe culturally specific objects, concepts or activities.
Finally, you can channel your inner Junot Diaz or Esme Wong and create a multilingual book without translation. Whilst you may lose in accessibility you may gain nuance of expression that is only possible in the languages in question (and the joy of multilingual readers), so if that feels like a good approach for your work, go to it.
Whether you’re writing about our world or a created one, embracing linguistic diversity gives you an amazing worldbuilding toolkit to really make your setting shine.