Low Valyrian

Source: https://medium.com/@harryaspinwall/a-peasants-guide-to-game-of-thrones-c6d1200adc5f

Low Valyrian is not a developed constructed language. The languages of Game of Thrones were created to the extent they were spoken in the show. These languages, namely Dothraki and High Valyrian, are spoken by several of the shows characters. The language of Low Valyrian is mentioned, but never spoken. The language is used by commoners, and the characters that are the focus of Game of Thrones are nobles and speak High Valyrian. Even though the language of Low Valyrian has not been invented, we can infer that in the world that Game of Thrones takes place, it is likely a more developed version of High Valyrian due to its higher usage.