Players will start out knowing the language of their homeland. Mages, sorcerers, clerics, and paladins (generally all learned classes) as well as players of noble descent will know Ambracian. Elves will know Zaori. These languages replace the Elven languages and Common in D&D 5.0.
Since the campaign starts out in Capet, assume that all characters are at least nominally fluent in Angevin.