His successors were less successful. Cyrus's unstable son, Cambyses II, conquered Egypt but later committed suicide during a revolt led by a priest, Gaumata, who usurped the throne until overthrown in 522 by a member of a lateral branch of the Achaemenid family, Darius I (also known as Darayarahush or Darius the Great). Darius attacked the Greek mainland, which had supported rebellious Greek colonies under his aegis, but as a result of his defeat at the Battle of Marathon in 490 was forced to retract the limits of the empire to Asia Minor.
The Achaemenids thereafter consolidated areas firmly under their control. It was Cyrus and Darius who, by sound and farsighted administrative planning, brilliant military maneuvering, and a humanistic worldview, established the greatness of the Achaemenids and in less than thirty years raised them from an obscure tribe to a world power.
The quality of the Achaemenids as rulers began to disintegrate, however, after the death of Darius in 486. His son and successor, Xerxes, was chiefly occupied with suppressing revolts in Egypt and Babylonia. He also attempted to conquer the Greek Peloponnesus, but encouraged by a victory at Thermopylae, he overextended his forces and suffered overwhelming defeats at Salamis and Plataea. By the time his successor, Artaxerxes I, died in 424, the imperial court was beset by factionalism among the lateral family branches, a condition that persisted until the death in 330 of the last of the Achaemenids, Darius III, at the hands of his own subjects.
The Achaemenids were enlightened despots who allowed a certain amount of regional autonomy in the form of the satrapy system. A satrapy was an administrative unit, usually organized on a geographical basis. A satrap (governor) administered the region, a general supervised military recruitment and ensured order, and a state secretary kept official records. The general and the state secretary reported directly to the central government. The twenty satrapies were linked by a 2,500-kilometer highway, the most impressive stretch being the royal road from Susa to Sardis, built by command of Darius. Relays of mounted couriers could reach the most remote areas in fifteen days. Despite the relative local independence afforded by the satrapy system however, royal inspectors, the "eyes and ears of the king," toured the empire and reported on local conditions, and the king maintained a personal bodyguard of 10,000 men, called the Immortals.
The language in greatest use in the empire was Aramaic. Old Persian was the "official language" of the empire but was used only for inscriptions and royal proclamations.
Next Page: Darius
Data as of December 1987
Source: Library of Congress Country Studies
*Jona Lendering points out that a 547/546 date for the fall of Croesus is based on the Nabonidus Chronicle whose reading is uncertain. Rather than Croesus it may have been the ruler of Uratu. Lendering says the fall of Lydia should be listed as the 540s.
**He also advises that cuneiform sources start to mention Cambyses as sole ruler in August 530, so the date of his death the following year is wrong.