These are the various constructed language projects which I have been working on, to various degrees.
Modern Arvandran is the primary language of the country of Arvandra. Old Arvandran is the ancestral form of Modern Arvandran, and which transmuted into Modern Arvandran around 500 years ago.
"Desert Tongue" is a generic phrase used to name the family of closely related languages used by the desert tribes which occupy the lands north-east of Arvandra.
The Northern Empire exists far to the north of Arvandra, and its primary language is in an entirely different language family than Arvandran.
In all of the lands known to the people of Arvandra, the dominant sentient races include Humans, Elves and Dwarves. Other sentient species, such as Dragons, also inhabit the planet, but for their own reasons have elected to remain apart and independent of the affairs of the humanoid races. But it has been discovered that in ancient times, perhaps prior to the emergence of sentient humanoid species, there was a race of sentient reptilian bipeds. Gradually, through the efforts of explorers and archaelogists, more is becoming known of these lizardly fore-runners, including glimpses into their spoken language.