the Median Empire. However, this interpretation clearly conflicts with Herodotus' information on Achaemenid military rosters. Death of Cyrus During the 6th century BCE, the Massagetae had to face the successor of the Median Empire, the newly formed Persian Achaemenid Empire, whose founder, Cyrus II, carried out a campaign against them in 530 BCE. According to Herodotus, Cyrus captured a Massagetaean camp by ruse, after which the Massagetae queen Tomyris led the tribe's main force against the Persians, defeated them, killed Cyrus, and placed his severed head in a sack full of blood. According to another version of the death of Cyrus recorded by Ctesias, it was the Derbices, who were the tribe against whom Cyrus died in battle: according to this version, he was mortally wounded by the Derbices and their Indian allies, after which Cyrus's ally, the king Amorges of the , intervened with his own army and helped the Persian soldiers defeat the Derbices, following which Cyrus endured for three days, during which he organised his empire and appointed Spitaces son of Sisamas as satrap over the Derbices, before finally dying. The reason why the Derbices, and not the Massagetae, are named as the people against whom Cyrus died fighting is because the Derbices were members or identical with the Massagetae. According to Strabo, Cyrus died fighting against the Saka (of which the Massagetae were a group), and according to Quintus Curtius Rufus he died fighting against the Abiae. The Babylonian scribe Berossus, who lived in 3rd century BCE, instead recorded that Cyrus died in a battle against the Dahae; according to the Iranologist Muhammad Dandamayev, Berossus identified the Dahae rather than the Massagetae as Cyrus's killers because they had replaced the Massagetae as the most famous nomadic tribe of Central Asia long before Berossus's time; although some scholars identified the Dahae as being identical with the Massagetae or as one of their sub-groups. Achaemenid rule Little more is known about the Massagetae after the war with Cyrus. By around 520 BCE and possibly earlier, they were ruled by a king named Skuⁿxa, who rebelled against the Persian Empire until one of the successors of Cyrus, the Achaemenid king Darius I, carried out a campaign against the Sakas from 520 to 518 BCE during which he conquered the Massagetae/, captured Skuⁿxa, and replaced him with a ruler who was loyal to Achaemenid power. According to Polyaenus, Darius fought