It was in the case of Crœsus that the Greeks were first called upon to deal with a tolerably large barbaric aggregate under a warlike and enterprising prince, and the result was such as to manifest the inherent weakness of their political system, from its incapacity of large combination. The separated autonomous cities could only maintain their independence either through similar disunion on the part of barbaric adversaries, or by superiority on their own side of military organization as well as of geographical position. The situation of Greece proper and of the islands was favorable to the maintenance of such a system,—not so the shores of Asia with a wide interior country behind. The Ionic Greeks were at this time different from what they became during the ensuing century, little inferior in energy to Athens or to the general body of European Greeks, and could doubtless have maintained their independence, had they cordially combined. But it will be seen hereafter that the Greek colonies,—planted as isolated settlements, and indisposed to political union, even when neighbors,—all of them fell into dependence so soon as attack from the interior came to be powerfully organized; especially if that organization was conducted by leaders partially improved through contact with the Greeks themselves. Small autonomous cities maintain themselves so long as they have only enemies of the like strength to deal with: but to resist larger aggregates requires such a concurrence of favorable circumstances as can hardly remain long without interruption. And the ultimate subjection of entire Greece, under the kings of Macedon, was only an exemplification on the widest scale of this same principle. The Lydian monarchy under Crœsus, the largest with which the Greeks had come into contact down to that moment, was very soon absorbed into a still larger,—the Persian; of which the Ionic Greeks, after unavailing resistance, became the subjects. The partial sympathy and aid which they obtained from the independent or European Greeks, their western neighbors, followed by the fruitless attempt on the part of the Persian king to add these latter to his empire, gave an entirely new turn to Grecian history and proceedings. First, it necessitated a degree of central action against the Persians which was foreign to Greek political instinct; next it opened to the noblest and most enterprising section of the Hellenic name,—the Athenians,—an opportunity of placing themselves at the head of this centralizing tendency: while a concurrence of circumstances, foreign and domestic, imparted to them at the same time that extraordinary and many-sided impulse, combining action with organization, which gave such brilliancy to the period of Herodotus and Thucydidês. It is thus that most of the splendid phenomena of Grecian history grew, directly or indirectly, out of the reluctant dependence in which the Asiatic Greeks were held by the inland barbaric powers, beginning with Crœsus.