Cyrus the Great (reigned 550-530 BC) was the founder of the Persian Empire. His reign witnessed the first serious contacts between Persians and Greeks and the permanent loss of political power by the peoples of the old centers of power in Mesopotamia.

In the new Median Empire, which shared with Babylon the spoils of the fallen Assyrian power, the Persians were a subordinate group, though closely related to the Medes and speaking a similar Indo-European language. They were ruled by their own local kings, and one of these married a daughter of the Median king Astyages; their son was Cyrus. Astyages seems not to have been popular, and when, in 550 B.C., Cyrus revolted, Astyages's own troops went over to Cyrus. The Median Empire thus became the Persian Empire. It is worth noting that Cyrus treated his defeated grandfather with honor and that instead of sacking Ecbatana, the...