> She adds, “The Greeks were obsessed with being Greeks,” considering all those who didn’t speak the language “barbarians.”
But "barbarian" meant something like "speaking another language".
But "barbarian" meant something like "speaking another language".
They however had no ideas about the inferiority of those (except that they preferred their own lifestyles which considered free-er).
Ancient slavery also was not about race, but about e.g. losing the battle and being caught or debt. Greeks could be (and often were) slaves to other Greeks.
"barbarbar" ~ "blahblahblah"
I don't think this is right. "Blah blah" implies someone who is overly talkative. "bar bar" [1] is an onomatopoieia of someone speaking a non-Greek language, like "arf arf" is for a dog.
I'm not even sure it has the meaning of "speaking gibberish" that you give it. I think it was literally just the way that some ancient language that was not Greek sounded to Greek ears. A bit like with the Swedish chef in Muppet show.
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[1] Actually, "var var". In Greek it's "βάρβαρος", pronounced "varvaros".
Did the Greeks use it frequently to describe any one people in particular?
In Homer there is no "barbarian"; only "barbar-speaking". But by the time of Aeschylus, it was a noun denoting people speaking non-Greek. There was also the corresponding verb that meant "speak a foreign language" but also "speak broken Greek / make lots of errors speaking (Greek)".
In Roman times, "barbarian" meant anyone who was not Roman or Greek.
It does not mean such people do not posses intelligence for this, it's just a cultural difference they might choose to keep their thoughts to themselves or see no point in convincing others through discourse if the power is established through sword.