Encounter-a-Day

The concept of a lingua franca is very important. In the real world, if you take two people completely at random, the chances of them sharing the same language– never mind a mother tongue or another language they’re both completely fluent in– is damn near zero. A Swiss pilot landing in Cairo, Egypt has to be able to communicate effectively with the tower, and both of them will speak English because it’s the lingua franca of the air industry. It’s not either one’s mother tongue, but particularly with respect to aeronautics both of them are expected to know how to communicate effectively in English.

German used to be the lingua franca of science and mathematics because so many of the best journals in the field were published in German. French was the lingua franca of Diplomacy until World War II. In modern days, English is the lingua franca of programming, diplomacy and business. Latin used to be the lingua franca of academia.

This concept can be extended to your fantasy games and add a bit of flavor. Rather than having one common tongue, have several for different purposes. Mionese, the language of the mighty Mion empire, might be the lingua franca of politics and diplomacy. Any character expecting to interact with nobility had best know how to speak Mionese or he’ll look terribly uncouth, if he’s not dismissed outright. Similarly, there could be a different language which is commonly used in arcane writings and a third used most often by merchants.

The important thing to note here is that these languages weren’t invented to be international languages in their fields; this phenomenon arises naturally because one particular country or region will frequently dominate a particular field. It’s only natural that their language becomes the de facto standard in that field. Depending on how deeply ingrained it is, a character might have a hard time dealing in that field without it or the character might even be actively ostracized.