"“The earliest mention of Iranians in historical sources is, paradoxically, of those settled on the Iranian plateau, not those still in Central Asia, their ancestral homeland. ‘Persians’ are first mentioned in the 9th century BC Assyrian annals: on one campaign, in 835 BC,… There are no literary sources for Iranians in Central Asia before the Old Persian inscriptions (Darius’s Bisotun inscription, 521-519 BC, ed. Schmitt) and Herodotus’ Histories (ca. 470 BC). ..."