-Skyrim
-High Rock
-Cyrodiil
-Hammerfell
-Morrowind
-Black Marsh
-Elsewyr
-Valenwood
-Alinor
I only came up with the languages of a few provinces: Alinor would speak French because they are the most civilized, Cyrodiil would speak Latin (I don't think that needs any explaining), Skyrim would speak Swedish.