"Barbarian" on it's original sense comes from the Greek word "barbaros", which was the opposite of the Greek word "polites" meaning "citizen". So originally, a "barbarian" referred to anyone who was not Greek. It's definition expanded from that to refer to anyone not Roman or Greek. The word itself comes from the onomatopoeia of the babbling that all non-Greek languages sounded like to the Greeks. I was always told non-Greeks sounded something like "bar ba bar ba bar" to the Greems, and this "barbarian" did not originally refer to uncivilized people, but rather non-Greek speakers. The Greeks would've referred to the Persians as barbarians, even though in many ways they were even a superior civilization than the Greeks.