The people and language is known as Itch-two-ans. The character known as Achaka may actually be from Achaka, as no one (other than Manny, who is untrustworhty at best, and later tosses out the name 'Pitch-three-ans') seems to actually know his name, and foreign knight answers Achaka to number of different qustions, including to the name of his homeland. Achaka could just be a word for "I don't understand" (However, Taskia does seem to confirm that her grand-father's name is Achaka).