Bardiya (died 522 bce) was a son of Cyrus the Great of Persia and possible king of Persia in 522 bce, although some accounts claim the king known as Bardiya was an impersonator of that son.
The Greek historian Herodotus and the Persian king Darius, in his inscription at Bīsitūn, state that Bardiya was murdered by his brother, Cambyses II, but was later successfully impersonated by Gaumata, a Magian, who was able to seize the throne when Cambyses died in 522 bce. The usurper reigned for only eight months, however, before he was slain by Darius and other Persian nobles suspicious of his origin. Certain modern historians consider that Darius, who succeeded to the throne, invented the story of Gaumata to justify his actions and that the murdered king had indeed been a son of Cyrus.