Even those who lived under the full-grown Athenian empire had before them no good accounts of the incidents between 479-450 B.C.; for we may gather from the intimation of Thucydides, as well as from his barrenness of facts, that while there were chroniclers both for the Persian invasion and for the times before, no one cared for the times immediately succeeding. Hence, the little light which has fallen upon this blank has all been borrowed—if we except the careful Thucydides—from a subsequent age; and the Athenian hegemony has been treated as a mere commencement of the Athenian empire: credit has been given to Athens for a long-sighted ambition, aiming from the Persian War downwards at results which perhaps Themistocles may have partially divined, but which only time and successive accidents opened even to distant view. But such systematic anticipation of subsequent results is fatal to any correct understanding, either of the real agents or of the real period; both of which are to be explained from the circumstances preceding and actually present, with some help, though cautious and sparing, from our acquaintance with that which was then an unknown future. When Aristides and Cimon dismissed the Lacedæmonian admiral Dorcis, and drove Pausanias away from Byzantium on his second coming out, they had to deal with the problem immediately before them; they had to complete the defeat of the Persian power, still formidable, and to create and organise a confederacy as yet only inchoate. This was quite enough to occupy their attention, without ascribing to them distant views of Athenian maritime empire.

In that brief sketch of incidents preceding the Peloponnesian War, which Thucydides introduces as “the throwing off of his narrative,” he neither gives, nor professes to give, a complete enumeration of all which actually occurred. During the interval between the first desertion of the Asiatic allies from Pausanias to Athens, in 477 B.C., and the revolt of Naxos in 466 B.C., he recites three incidents only: first, the siege and capture of Eion, on the Strymon, with its Persian garrison; next, the capture of Scyros, and appropriation of the island to Athenian cleruchs, or out-citizens; thirdly, the war with Carystus in Eubœa and reduction of the place by capitulation. It has been too much the practice to reason as if these three events were the full history of ten or eleven years. Considering what Thucydides states respecting the darkness of this period, we might perhaps suspect that they were all which he could learn about it on good authority: and they are all, in truth, events having a near and special bearing on the subsequent history of Athens herself; for Eion was the first stepping-stone to the important settlement of Amphipolis, and Scyros in the time of Thucydides was the property of outlying Athenian citizens, or cleruchs.

Still, we are left in almost entire ignorance of the proceedings of Athens, as conducting the newly established confederate force: for it is certain that the first ten years of the Athenian hegemony must have been years of most active warfare against the Persians. One positive testimony to this effect has been accidentally preserved to us by Herodotus, who mentions, that “before the invasion of Xerxes, there were Persian commanders and garrisons everywhere in Thrace and the Hellespont, all of whom were conquered by the Greeks after that invasion, with the single exception of Mascames, governor of Doriscus, who could never be taken, though many different Grecian attempts were made upon the fortress. Of those who were captured by the Greeks, not one made any defence sufficient to attract the admiration of Xerxes, except Boges, governor of Eion.” Boges, after bravely defending himself, and refusing offers of capitulation, found his provisions exhausted, and further resistance impracticable. He then kindled a vast funeral pile, slew his wives, children, concubines, and family, and cast them into it, threw his precious effects over the wall into the Strymon, and lastly, precipitated himself into the flames. His brave despair was the theme of warm encomium among the Persians, and his relatives in Persia were liberally rewarded by Xerxes. This capture of Eion, effected by Cimon, has been mentioned, as already stated, by Thucydides; but Herodotus here gives us to understand that it was only one of a string of enterprises, all unnoticed by Thucydides, against the Persians. Nay, it would seem from his language, that Mascames maintained himself in Doriscus during the whole reign of Xerxes, and perhaps longer, repelling successive Grecian assaults.

The valuable indication here cited from Herodotus would be of itself a sufficient proof that the first years of the Athenian hegemony were full of busy and successful hostility against the Persians. And in truth this is what we should expect: the battles of Salamis, Platæa, and Mycale, drove the Persians out of Greece, and overpowered their main armaments, but did not remove them at once from all the various posts which they occupied throughout the Ægean and Thrace. Without doubt, the Athenians had to clear the coasts and the islands of a great number of different Persian detachments: an operation never short nor easy, with the then imperfect means of siege, as we may see by the cases of Sestus and Eion; nor, indeed, always practicable, as the case of Doriscus teaches us. The fear of these Persians, yet remaining in the neighbourhood, and even the chance of a renewed Persian invading armament, formed one pressing motive for Grecian cities to join the new confederacy: while the expulsion of the enemy added to it those places which he had occupied. It was by these years of active operations at sea against the common enemy, that the Athenians first established that constant, systematic, and laborious training, among their own ships’ crews, which transmitted itself with continual improvements down to the Peloponnesian War: it was by these, combined with the present fear, that they were enabled to organise the largest and most efficient confederacy ever known among Greeks, to bring together deliberative deputies, to plant their own ascendency as enforcers of the collective resolutions, and to raise a prodigious tax from universal contribution. Lastly, it was by these same operations, prosecuted so successfully as to remove present alarm, that they at length fatigued the more lukewarm and passive members of the confederacy, and created in them a wish either to commute personal service for pecuniary contribution, or to escape from the obligation of service in any way. The Athenian nautical training would never have been acquired, the confederacy would never have become a working reality, the fatigue and discontents among its members would never have arisen, unless there had been a real fear of the Persians, and a pressing necessity for vigorous and organised operations against them, during the ten years between 477 and 466 B.C.

But after a few years several of the confederates becoming weary of personal military service, prevailed upon the Athenians to provide ships and men in their place, and imposed upon themselves in exchange a money payment of suitable amount. This commutation, at first probably introduced to meet some special case of inconvenience, was found so suitable to the taste of all parties that it gradually spread through the larger portion of the confederacy. To unwarlike allies, hating labour and privation, it was a welcome relief, while to the Athenians, full of ardour and patient of labour, as well as discipline, for the aggrandisement of their country, it afforded constant pay for a fleet more numerous than they could otherwise have kept afloat. It is plain from the statement of Thucydides that this altered practice was introduced from the petition of the confederates themselves, not from any pressure or stratagem on the part of Athens. But though such was its real source, it did not the less fatally degrade the allies in reference to Athens, and extinguish the original feeling of equal rights and partnership in the confederacy, with communion of danger as well as of glory, which had once bound them together.

The Athenians came to consider themselves as military chiefs and soldiers, with a body of tribute-paying subjects, whom they were entitled to hold in dominion, and restrict, both as to foreign policy and internal government, to such extent as they thought expedient, but whom they were also bound to protect against foreign enemies. The military force of these subject-states was thus in a great degree transferred to Athens, by their own act, just as that of so many of the native princes in India was made over to the English.

Under such circumstances several of the confederate states grew tired even of paying their tribute, and averse to continuance as members. They made successive attempts to secede, but Athens, acting seemingly in conjunction with the synod, repressed their attempts one after the other, conquering, fining, and disarming the revolters; which was the more easily done, since in most cases their naval force had been in great part handed over to her. As these events took place, not all at once, but successively in different years, the number of mere tribute-paying allies as well as of subdued revolters continually increasing, so there was never any one moment of conspicuous change in the character of the confederacy: the allies slid unconsciously into subjects, while Athens, without any predetermined plan, passed from a chief into a despot. By strictly enforcing the obligations of the pact upon unwilling members, and by employing coercion against revolters, she had become unpopular in the same proportion as she acquired new power, and that, too, without any guilt of her own. In this position, even if she had been inclined to relax her hold upon the tributary subjects, considerations of her own safety would have deterred her from doing so; for there was reason to apprehend that they might place their strength at the disposal of her enemies. It is very certain that she never was so inclined; it would have required a more self-denying public morality than has ever been practised by any state, either ancient or modern, even to conceive the idea of relinquishing voluntarily an immense ascendency as well as a lucrative revenue: least of all was such an idea likely to be conceived by Athenian citizens, whose ambition increased with their power, and among whom the love of Athenian ascendency was both passion and patriotism. But though the Athenians were both disposed and qualified to push all the advantages offered, and even to look out for new, we must not forget that the foundations of their empire were laid in the most honourable causes: voluntary invitation, efforts both unwearied and successful against a common enemy, unpopularity incurred in discharge of an imperative duty, and inability to break up the confederacy without endangering themselves as well as laying open the Ægean Sea to the Persians.

There were two causes, besides that which has just been adverted to, for the unpopularity of imperial Athens. First, the existence of the confederacy, imposing permanent obligations, was in conflict with the general instinct of the Greek mind, tending towards separate political autonomy of each city, as well as with the particular turn of the Ionic mind, incapable of that steady personal effort which was requisite for maintaining the synod of Delos, on its first large and equal basis. Next,—and this is the great cause of all,—Athens, having defeated the Persians, and thrust them to a distance, began to employ the force and the tribute of her subject-allies in warfare against Greeks, wherein these allies had nothing to gain from success, everything to apprehend from defeat, and a banner to fight for, offensive to Hellenic sympathies. On this head, the subject-allies had great reason to complain throughout the prolonged wars of Greek against Greek for the purpose of sustaining Athenian predominance: but on the point of practical grievances or oppression they had little ground for discontent and little feeling of actual discontent. Among the general body of citizens in the subject-allied cities, the feeling towards Athens was rather indifference than hatred: the movement of revolt against her proceeded from small parties of leading men, acting apart from the citizens, and generally with collateral views of ambition for themselves; and the positive hatred towards her was felt chiefly by those who were not her subjects.

It is probable that the same indisposition to personal effort, which prompted the confederates of Delos to tender money payment as a substitute for military service, also induced them to neglect attendance at the synod. But we do not know the steps whereby this assembly, at first an effective reality, gradually dwindled into a mere form and vanished. Nothing, however, can more forcibly illustrate the difference of character between the maritime allies of Athens, and the Peloponnesian allies of Sparta, than the fact that, while the former shrank from personal service, and thought it an advantage to tax themselves in place of it, the latter were “ready enough with their bodies,” but uncomplying and impracticable as to contributions. The contempt felt by these Dorian landsmen for the military efficiency of the Ionians recurs frequently, and appears even to have exceeded what the reality justified: but when we turn to the conduct of the latter twenty years earlier, at the battle of Lade, in the very crisis of the Ionic revolt from Persia, we detect the same want of energy, the same incapacity of personal effort and labour, as that which broke up the confederacy of Delos with all its beneficial promise. To appreciate fully the indefatigable activity and daring, together with the patient endurance of laborious maritime training, which characterised the Athenians of that day, we have only to contrast them with these confederates, so remarkably destitute of both. Amidst such glaring inequalities of merit, capacity, and power, to maintain a confederacy of equal members was impossible: it was in the nature of things that the confederacy should either break up, or be transmuted into an Athenian empire.

It has already been mentioned that the first aggregate assessment of tribute, proposed by Aristides, and adopted by the synod at Delos, was four hundred and sixty talents in money (about £92,000, or $460,000). At that time many of the confederates paid their quota, not in money but in ships; but this practice gradually diminished, as the commutations above alluded to, of money in place of ships, were multiplied, while the aggregate tribute, of course, became larger. It was no more than six hundred talents at the commencement of the Peloponnesian War, forty-six years after the first formation of the confederacy; from whence we may infer that it was never at all increased upon individual members during the interval. For the difference between four hundred and sixty talents and six hundred admits of being fully explained by the numerous commutations of service for money, as well as by the acquisitions of new members, which doubtless Athens had more or less the opportunity of making. It is not to be imagined that the confederacy had attained its maximum number, at the date of the first assessment of tribute: there must have been various cities, like Sinope and Ægina, subsequently added.