Although the Iranian kings were ruthless in their conquests, they were not cruel by comparison with their neighbors and predecessor.

Toleration rather than intimidation was the keynote of their imperial policy. The Ackaemenid kings sought to annex the conquered peoples to the empire on favorable terms.

Iranian rule was less rigid than Assyrian, and so less objectionable. Babylon submitted to Cyrus without a fight. Many Babylonians preferred his rule to that of Naabonidus, the last king. Instead of destroying Babylon as Sennacherib had done, Cyrus honored it by making the city one of his several capitals.

The Iranian empire was organized into Satrapies (Provinces) by Darius I (Reigned 521-486 BC), the third king of Persia. Each satrapy had its Satrap (Governor). Darius first, mindful perhaps of Cyrus's past experience, was suspicious of satraps who might grow too powerful. Therefore, alongside each satrap he appointed a general and a secretary of state.

With the power divided among them, the three officials had to report directly to the king. His personal inspectors visited them regularly, accompanied by a troop of soldiers.

The Iranians took over and extended the Assyrian road system. The Royal Road built by Darius, ran 2500 kilometers from Sardis to Susa and was used by traders as well as soldiers.

Except for Persia itself all satrapies paid taxes to the central government. In previous empires taxes and tribute had been paid in kind. But now Money.-a much more convenient form of exchange- was coming into use. Darius I issued a gold coin - the Daric. Soon, it passed as a currency even outside the empire.