The great multitude of nomad tribes which wandered on the borders of the Persian empire greatly facilitated the assembling of mighty armaments. These tribes readily engaged in such enterprises, either for pay or allured by the hope of plunder. As the Baskirs and Calmucks follow the Russian armies, so did the Mardi, Pericanii, and others, those of Cyrus; and the more widely the dominion of the Persians was extended, the greater became the number of such auxiliaries. The Persians stood the more in need of their aid as their own cavalry was always heavy-armed. With them, as with the Parthians, both man and horse were armed in mail, though, strictly speaking, this appears to have been a distinction confined to a certain number, and the greater part seem to have had no defensive armour, and thus served to swell the carnage which the Greeks wrought among them after the victory of Platæa.
The foregoing sections must have served to explain the way in which these forces subsisted in the provinces. Each province was obliged to furnish to the governor what was necessary to their maintenance, in kind, and the governor caused what was so collected to be distributed among the soldiers. Payment in money was made only to the Grecian auxiliaries, who could not otherwise have been kept together, having been accustomed to the same in their own country; the Persians were bound to serve without pay, and the nomad races of Central Asia, many of whom had never even seen coined money, were as little disposed to require remuneration in that shape as are at the present day many of the auxiliaries of the Russian armies.
In a warlike nation, a military command always confers great distinction, being often regarded as more honourable than the civil magistracies; and this was the case among the Persians. The Myriarchs (commanders of tens of thousands) and Chiliarchs (commanders of thousands) enjoyed a distinguished rank, and the officers above them, the generals, were among the most illustrious of the nation. Of the generality of these we are expressly told that they belonged to the family of the Achæmenidæ, or at all events to the tribe of the Pasargadæ, or were connected by marriage with the royal house, and consequently the officers of rank consisted principally of the king’s kinsmen. Among these generals themselves, however (of whom there were usually several in an army), there existed gradations of rank; and if a king’s son was appointed generalissimo, this was understood as equivalent to his nomination as successor.
Hitherto we have confined our remarks to the troops which were regularly maintained by the Persians to defend the conquered provinces. With the exception of those raised among the Persians themselves, these appear, from what has been stated, to have consisted of mercenary troops, to the exclusion of the natives of the provinces themselves; nevertheless, the latter were by no means free from all military service, but were summoned on occasions of extraordinary expeditions undertaken for the extension of the empire. On such emergencies general mandates were issued throughout all the vast dominion of Persia, the nations of the East and West were gathered together in herds, and one of the most extraordinary spectacles ensued which the history of the world has recorded, and the more deserving of our regard for the accuracy with which Herodotus has described the armament of Darius, and still more that of Xerxes.
When the Persians began their career as conquerors they adopted, and always maintained, the custom that the conquered nations should swell the numbers of their host, and accompany them in their more remote expeditions. When, however, their empire had become consolidated and organised, and stretched from the Indus to the Mediterranean, the drawing together of forces so widely disseminated must have become burdened with endless difficulties, and would consequently, on occasions of minor importance (such as slight internal disturbances, or trifling wars,) have been as futile as impossible. On extraordinary occasions, however, whether of great national undertakings for the aggrandisement of the empire, or of formidable invasions from without, the custom was revived of mustering the whole force of the empire, as is proved by the mighty expeditions of Darius Hystaspes, of Xerxes, and the last Darius.
Even the preliminary steps to such armaments were of vast magnitude. The king’s mandate was addressed to all nations, and specified the number of men, horses, and ships, or the amount of provisions to be furnished by each. The commotion which was excited in all Asia by the preparations made for the expedition of Xerxes, lasted for four years. Time was necessary to enable the remote nations to send in their contingent.