Libya was a satrapy of the Achaemenid Empire according to King Darius I of Persia Naqshe Rustam and King Xerxes I of Persia' Daiva inscription. It is also mentioned as being part of the 6th district by Herodotus, which also included Cyrene, a Greek colony in Libya. When King Cambyses II of Persia conquered Egypt, the king of Cyrene, Arcesilaus III, sided with Persia. When he was killed trying to maintain power, Queen Pheretima invited the Persians to take Cyrene. The satrap of Egypt, Aryandes, accepted, and once the conquest was complete, a puppet king, Battus IV, was installed. It is possible that Cyrene gained independence with the rebellion of Egypt in 404 BCE, but ultimately, Achaemenid control of the region was lost after Alexander's conquests.