On the matter of "Aryan" cultures... It is universally accepted to the linguistic/historian community (I mean the academic one, of course) that the term Aryan or Indo-aryan is linked with a certain linguistic group that refers to the Sanscrit, the Avest and the (oddly minor asian originated) Mittani language families.
I quote a formidable article from wikipedia :
" Aryan is an English word derived from the Vedic Sanskrit and Avestan term arya, meaning "noble" or "lord". In the 19th century, the term was often used to refer to what we now call the Proto-Indo-Europeans. Aryan currently refers to the Indo-Iranian language sub-family, or to its Indian sub-branch known as Indo-Aryan.
The Aryan (Indo-Iranian) proto-language evolved into the family of Indo-Iranian languages, of which the oldest known members are Sanskrit and Avestan (and the fragmentary Mitanni language).
The term has also been used to refer to a "race", originally in the sense of a distinct population. Ancient writers such as Herodotus used it for the Iranian people. Herodotus wrote: "In ancient times, the Greeks called Iranians "Kaffe", but they were renowned as Aryans among themselves and their neighbors". In another part of his book, Herodotus writes that the Medians were known as Aryans during a certain period. So in two of the oldest surviving written documents, the race of the Iranians have been mentioned as Aryan.
19th century writers used it as name for Indo-Europeans peoples as a whole. It can also be used as an indication for the religious origin of the Hindus. To prevent confusion because of its several meanings, the term is often often avoided today, and replaced by the well-defined Proto-Indo-European, Proto-Indo-Iranian, Indo-Iranian, Iranian or Indo-Aryan. "
About the barbarians, interesting is the following quote from the classic, superb and especially recommended "In Search of the Indo-Europeans"; Language, Archaeology and Myth by J.P. Mallory (1989, Thames and Hudson Ltd., London). (greek : ,1989) :
".... The common linguistic heritage of the Indo-Europeans was only discovered in the eighteenth century and it has seldom, if ever, impinged on the behavior of the different Indo-Europeans. History provides little evidence that different Indo-European groups ever recognized their mutual kinship. If the ancient Greeks disparaged an Indian as barbaros, the Indian dug into the same linguistic legacy to dismiss his non-Aryan neighbors with precisely the same word, barbaras. ...."