Archaeological excavations also indicate that, by the 6th century BC, similar experimentation had taken place among the Iranian peoples inhabiting the Khwarezm region and Aral Sea basin, such as the Massagetae, Dahae and Saka. While the offensive weapons of these prototype cataphracts were identical to those of the Assyrians, they differed in that not only the rider but also the head and flanks of the horse were protected by armor. Whether this development was influenced by the Assyrians, as Rubin postulates, or perhaps the Achaemenid Empire, or whether they occurred spontaneously and entirely unrelated to the advances in heavily armored cavalry made in the Ancient Near East, cannot be discerned by the archaeological records left by these mounted nomads.