As was also the case for the fourth century Roman identification of Zoroaster's patron with the late-6th century BCE father of Darius I (see below) – the identification of Vishtaspa as a grandfather of "Ardashir" (Artaxerxes I/II) was once perceived to substantiate the "traditional date" of Zoroaster, which places the prophet in the 6th century BCE. The traditional descriptions of Vishtaspa's ancestors as having chariots (a description that puts them fully in the Bronze Age) also contribute to the academic debate on the dating of Zoroaster; for a summary of the role of Vishtaspa's ancestors in this issue, see .