The Achaemenid Empire founded by Cyrus the Great (550-530 BCE), 1 expanded by his successors, Cambyses (530-522) and most importantly Darius the Great (522-486), was conquered by Alexander the Great between 334 and 323. After the wars between the successors of the Macedonian conqueror, also known as the Diadochi, the empire imploded into several competing kingdoms (the Hellenistic kingdoms). From a geopolitical global perspective, the establishment of the empire of the Great Kings put an end to a very long period of territorial divisions among several kingdoms and empires, such as those existing around 550 (Pharaonic Egypt, the Lydian Kingdom in Asia Minor, the neo-Babylonian kingdom in Mesopotamia and in the Fertile Crescent, the Median kingdom in the surroundings of Hamadan/Ecbatana, etc.). The Achaemenid historical phase represents thus a singular moment in the longue durée: it is the first and last time in history that these peoples and countries were united within a unitary state structure for more than two centuries. This would later be called the Persian-Achaemenid Empire, in line with the name of the reigning dynasty (Map 1.1).To the great surprise of his contemporaries, Alexander the Great succeeded in seizing the empire following four major battles. One of which, the Battle of Gaugamela in October 331, made possible the consequent capturing of the large royal residencies situated in the Babylonian and Elamite plains (Babylon, Susa) as well as those situated on the Persian (Persepolis, Pasargadae) and Median plateau (Ecbatana). Since antiquity, Alexander's victory traditionally served as a proof to the weakness of state control in the Achaemenid region and an indication of its irremediable decadence. In line with the fourth-century Plato and Xenophon views, this decadence is proposed as starting with the death of Cyrus in 530. 2 In modern Europe, one of the most popular thesis was to 1 Hereafter all dates are before common era (BCE) unless indicated otherwise. 2 See Briant 2002b, where the texts are quoted and commented.