Here´s a little question...

In my copy of the Swedish translation Atlas Hisorique. L´Histoire de l´Humanité de la Préhistoire á nos jours I found in the timeline a quick little reference

First Century BC: The Hunns from Mongolia became a shield agains the indoeuropean Yvezhi who returned back to Central Asia where they destroyed the Hellenism...

Who are thise Yvezhi??

Have anyone heard of them?

Thanx!

Do you mean these guys?

http://en.wikipedia.org/wiki/Yuezhi

Yeah! I think so!

Is there anyone who know what impact they had on Greece and Rome. The article say they where an Indoeuropean culture, how do we know that?

Not to Greece an dRome as such, but to the Hellenistic kingdoms in Bactria and northern India--better known as the Greco-Bactrian and Greco-Indian cultures. You'd probably be able to get more information about them by Googling about the White Huns and the Kushans as well as the Yuezhi (or "Yueh-chih" in Wade-Giles) proper.