Durian Tongues
Illyrian
Illyrian, a close relative of Koramian, is spoken almost exclusively in Illyria and Dakra, in the far north of Duria
Koramian
Koramian is spoken primarily in Koramia, though there are no small number of speakers on Stormward Isle and Tamerynd. It is the language of the peasantry of Ciritasnia and is presumably spoken by whatever sentients still exist on the Black Isle. Koramian is something of an amalgamation of a large variety of languages, with strong influences from Zetian and Narbonais, due to its long history of conquest by the Empire.
Pelusian
Pelusian is spoken primarily in Pelusia. Of the Durian Tongues, it tends to be the most unique, with a slightly different grammatical structure than other Durian Tongues. Most scholars suggest that this is because it developed in the high valleys of Pelusia with almost no contact with the outside world for centuries.
Nagosi
Nagosi is spoken primarily in Nagos, though it is something of a minor trade language to the human nations of the Sea of Blades. Scholars familiar with elemental languages suggest that there is some Aquan influences on Nagosi, but this controversial theory is by no means proven.