at first consisted mainly of cavalry, and owed much of their success to
the consequent ease and rapidity of their movements. The warlike
Persians constantly extended their power by fresh conquests, and for
some time remained a distinctly conquering and military race, attaining
their highest power under Cyrus and Cambyses. Cyrus seems to have been
the founder of a comprehensive military organization, of which we gather
details from Xenophon and other writers. To each province was allotted a
certain number of soldiers as standing army. These troops, formed
originally of native Persians only, were called the king's troops. They
comprised two classes, the one devoted exclusively to garrisoning towns
and castles, the other distributed throughout the country. To each
province was appointed a military commander, responsible for the number
and efficiency of the troops in his district, while the civil governor
was answerable for their subsistence and pay. Annual musters were held,
either by the king in person or by generals deputed for the purpose and
invested with full powers. This organization seems to have fully
answered its original purpose, that of holding a vast empire acquired by
conquest and promptly repelling inroads or putting down insurrections.
But when a great foreign war was contemplated, the standing army was
augmented by a levy throughout the empire. The extent of the empire made
such a levy a matter of time, and the heterogeneous and unorganized mass
of men of all nations so brought together was a source of weakness
rather than strength. Indeed, the vast hosts over which the Greeks
gained their victories comprised but a small proportion of the true
Persians. The cavalry alone seems to have retained its national
character, and with it something of its high reputation, even to the
days of Alexander.