The Persian kings are called Achaemenid, as they claimed descent from a legendary King Achaemenes of around the eighth century BCE. The Persians expanded their power by first conquering, then absorbing their Median kinsmen.
The early kings, beginning with Cyrus:
Cyrus the Great (c 560/559-530BCE) was the king who defeated the Median king, Astyages (c 585 – 550), and afterwards conquered the Lydians and the Babylonians, making Persia a great power.
Bardia (also known as Smerdis) 522
Darius I (522-486)
Xerxis I (486-465), the king who attempted to invade Greece
Artaxerxes I (465-424)