About the time of Elamites, the indo European Aryan tribes entered Iran from north, including Medes who settled in northwest, Persians in south near Shiraz and Parthians who chose northeast to settle. The Medes established their capital in Ecbatana near Hamedan, Deioces the median ruler accompanied with the Babylonian king could put an end to the Assyrian cruel kingship. Cyrus the Great, a noble peace lover man rose from Persians and took up the control of median lands and established the greatest empire in the world. Pasargadae was the first capital of achaemenid Empire and capital of Darius I successor of Cyrus the great was at Susa. He built Persepolis including many palaces near Shiraz which represents the glory of Persian architecture.
Achaemenid Empire has been named as the greatest and the most extensive Empire of the world. In Darius’s inscription, it is said that after removing the riots, Darius the Great divided the whole territory in 30 states (Satrapi). In this period 23 countries were dominated by Achaemenid Empire. From Indus valley in India to the Nile River in Egypt and Libya, also from Danube River in Europe to Central Asia, all were part of Iran’s territory.