"...But in fact, the enemies are led into battle by a king with an Iranian name, Kavaṣa, belonging to the Iranian Kavi dynasty, their tribal names and nicknames all have Iranian counterparts or are known from Iranian and Greek sources to refer to Iranian communities. Moreover, their religion is described as having the typical characteristics of Mazdeism: without Indra, without Devas, without fire-sacrifice etc.. Very obviously, the enemies of the Vedic people at that time, when Rg-Vedic books 7 and 4 and the contemporaneous parts of books 1 and 9 were composed, were Iranian, not “black aboriginal”. This is attested from so many angles that one tends to wonder how this mistake could have been made at all, and how the true Iranian identity of the Dāsas (Greek Dahai) could have been missed."
January 1, 1970
https://en.wikiquote.org/wiki/Battle_of_the_Ten_Kings