The Iranian plateau was settled about 1500 BC by Aryan tribes, the most important of which were the Medes, who occupied the northwestern portion, and the Persians, who emigrated from Parsua, a land west of Lake Urmia, into the southern region of the plateau, which they named Parsamash or Parsumash. The first prominent leader of the Persians was the warrior chief Hakhamanish, or Achaemenes, who lived about 681 BC.
The Persians were dominated by the Medes until the accession to the Persian throne in 550 BC of Cyrus the Great. He overthrew the Median rulers, conquered the kingdom of Lydia in 546 BC and that of Babylonia in 539 BC and established the Persian Empire as the preeminent power of the world.