In the interval necessary for preparation, an attempt was made to throw the blame of commencing hostilities upon the Athenians by sending three several embassies to Athens with demands of such a nature as could not be accepted. In the assembly which was held at Athens to give a final answer to these demands, Pericles, who was now at the height of his power, urged the people to engage in the war, and laid down a plan for the conduct of it. He advised the people to bring all their movable property from the country into the city, to abandon Attica to the ravages of the enemy, and not to suffer themselves to be provoked to give them battle with inferior numbers, but to expend all their strength upon their navy, which might be employed in carrying the war into the enemy's territory, and in collecting supplies from subject States; and further, not to attempt any new conquest [p. 1193] while the war lasted. His advice was adopted, and the Spartan envoys were sent home with a refusal of their demands, but with an offer to refer the matters in difference to an impartial tribunal, an offer which the Lacedaemonians had no intention of accepting. After this the usual peaceful intercourse between the rival States was discontinued. Thucydides (ii. 1) dates the beginning of the war from the early spring of the year B.C. 431, the fifteenth of the thirty years' truce, when a party of Thebans made an attempt, which at first succeeded, but was ultimately defeated, to surprise Plataea.
The truce being thus openly broken, both parties addressed themselves to the war. The Peloponnesian confederacy included all the States of Peloponnesus except Achaia (which joined them afterwards) and Argos, and without the Peloponnesus, Megaris, Phocis, Locris, Boeotia, the island of Leucas, and the cities of Ambracia and Anactorium. The allies of the Athenians were Chios and Lesbos, besides Samos and the other islands of the Aegaean which had been reduced to subjection (Thera and Melos, which were still independent, remained neutral), Plataea, the Messenian colony in Naupactus, the majority of the Acarnanians, Corcyra, Zacynthus, and the Greek colonies in Asia Minor, in Thrace and Macedonia, and on the Hellespont. The resources of Sparta lay chiefly in her land forces, which, however, consisted of contingents from the allies, whose period of service was limited; the Spartans were also deficient in money. The Athenian strength lay in the fleet, which was manned chiefly by foreign sailors, whom the wealth collected from the allies enabled them to pay. Thucydides informs us that the cause of the Lacedaemonians was the more popular, as they professed to be deliverers of Greece, while the Athenians were fighting in defence of a dominion which had become odious through their tyranny, and to which the States which yet retained their independence feared to be brought into subjection.
In the summer of the year B.C. 431 the Peloponnesians invaded Attica under the command of Archidamus, king of Sparta. Their progress was slow, as Archidamus appears to have been still anxious to try what could be done by intimidating the Athenians before proceeding to extremities. Yet their presence was found to be a greater calamity than the people had anticipated; and when Archidamus made his appearance at Acharnae, they began loudly to demand to be led out to battle. Pericles firmly adhered to his plan of defence, and the Peloponnesians returned home. Before their departure the Athenians had sent out a fleet of a hundred sail, which was joined by fifty Corcyrean ships, to waste the coasts of Peloponnesus; and towards the autumn Pericles led the whole disposable force of the city into Megaris, which he laid waste. In the same summer the Athenians expelled the inhabitants of Aegina from their island, which they colonized with Athenian settlers. In the winter there was a public funeral at Athens for those who had fallen in the war, and Pericles pronounced over them an oration, the substance of which is preserved by Thucydides (ii. 35-46). In the following summer (B.C. 430) the Peloponnesians again invaded Attica under Archidamus, who now entirely laid aside the forbearance which he had shown the year before, and left scarcely a corner of the land unravaged. This invasion lasted forty days. In the meantime, a grievous pestilence broke out in Athens, and raged with the more virulence on account of the crowded state of the city. Of this terrible visitation Thucydides, who was himself a sufferer, has left a minute and apparently faithful description (ii. 46 foll.). The murmurs of the people against Pericles were renewed, and he was compelled to call an assembly to defend his policy. He succeeded so far as to prevent any overtures for peace being made to the Lacedaemonians, but he himself was fined, though immediately afterwards he was reëlected general. While the Peloponnesians were in Attica, Pericles led a fleet to ravage the coasts of Peloponnesus. In the winter of this year Potidaea surrendered to the Athenians on favourable terms ( Thuc.ii. 70). The next year (B.C. 429), instead of invading Attica, the Peloponnesians laid siege to Plataea. The brave resistance of the inhabitants forced their enemies to convert the siege into a blockade. In the same summer, an invasion of Acarnania by the Ambracians and a body of Peloponnesian troops was repulsed; and a large Peloponnesian fleet, which was to have joined in the attack on Acarnania, was twice defeated by Phormion in the mouth of the Corinthian Gulf. An expedition sent by the Athenians against the revolted Chalcidian towns was defeated with great loss.
In the preceding year (B.C. 430) the Athenians had concluded an alliance with Sitalces, king of the Odrysae in Thrace, and Perdiccas, king of Macedon, on which occasion Sitalces had promised to aid the Athenians to subdue their revolted subjects in Chalcidicé. He now collected an army of 150,000 men, with which he first invaded Macedonia, to revenge the breach of certain promises which Perdiccas had made to him the year before, and afterwards laid waste the territory of the Chalcidians and Bottiaeans, but he did not attempt to reduce any of the Greek cities. About the middle of this year Pericles died. The invasion of Attica was repeated in the next summer (B.C. 428), and immediately afterwards all Lesbos except Methymné revolted from the Athenians, who laid siege to Mitylené. The Mitylenaeans begged aid from Sparta, which was promised, and they were admitted into the Spartan alliance. In the same winter a body of Plataeans, amounting to 220, made their escape from the besieged city in the night, and took refuge in Athens. In the summer of B.C. 427 the Peloponnesians again invaded Attica, while they sent a fleet of forty-two galleys, under Alcidas, to the relief of Mitylené. Before the fleet arrived Mitylené had surrendered, and Alcidas, after a little delay, sailed home. In an assembly which was held at Athens to decide on the fate of the Mitylenaeans, it was resolved, at the instigation of Cleon, that all the adult citizens should be put to death, and the women and children made slaves; but this barbarous decree was repealed the next day. The land of the Lesbians (except Methymné) was seized and divided among Athenian citizens, to whom the inhabitants paid a rent for the occupation of their former property. In the same summer the Plataeans surrendered; they were massacred, and their city was given up to the Thebans, who razed it to the ground. In the year B.C. 426 the Lacedaemonians were deterred from invading Attica by earthquakes. An expedition against Aetolia, under the [p. 1194] Athenian general Demosthenes, completely failed; but afterwards Demosthenes and the Acarnanians routed the Ambracians, who nearly all perished. In the winter (B.C. 426-425) the Athenians purified the island of Delos, as an acknowledgment to Apollo for the cessation of the plague.
At the beginning of the summer of B.C. 425 the Peloponnesians invaded Attica for the fifth time. At the same time the Athenians, who had long directed their thoughts towards Sicily, sent a fleet to aid the Leontini in a war with Syracuse. Demosthenes accompanied this fleet, in order to act, as occasion might offer, on the coast of Peloponnesus. He fortified Pylus on the coast of Messenia, the northern headland of the modern Bay of Navarino. In the course of the operations which were undertaken to dislodge him, a body of Lacedaemonians, including several noble Spartans, got blockaded in the island of Sphacteria, at the mouth of the bay, and were ultimately taken prisoners by Cleon and Demosthenes. Pylus was garrisoned by a colony of Messenians, in order to annoy the Spartans. After this event the Athenians engaged in vigorous offensive operations, of which the most important was the capture of the island of Cythera by Nicias early in B.C. 424. This summer, however, the Athenians suffered some reverses in Boeotia, where they lost the battle of Delium, and on the coasts of Macedonia and Thrace, where Brasidas, among other exploits, took Amphipolis. The Athenian expedition to Sicily was abandoned, after some operations of no great importance, in consequence of a general pacification of the island, which was effected through the influence of Hermocrates, a citizen of Syracuse. In the year B.C. 423 a year's truce was concluded between Sparta and Athens, with a view to a lasting peace. Hostilities were renewed in B.C. 422, and Cleon was sent to cope with Brasidas, who had continued his operations even during the truce. A battle was fought between these generals at Amphipolis, in which the defeat of the Athenians was amply compensated by the double deliverance which they experienced in the death both of Cleon and Brasidas. In the following year (B.C. 421) Nicias succeeded in negotiating a peace with Sparta for fifty years, the terms of which were a mutual restitution of conquests made during the war and the release of the prisoners taken at Sphacteria. This treaty was ratified by all the allies of Sparta except the Boeotians, Corinthians, Eleans, and Megarians. This peace never rested on any firm basis. It was no sooner concluded than it was discovered that Sparta had not the power to fulfil her promises, and Athens insisted on their performance. The jealousy of the other States was excited by a treaty of alliance which was concluded between Sparta and Athens immediately after the peace, and intrigues were commenced for the formation of a new confederacy, with Argos at the head. An attempt was made to draw Sparta into alliance with Argos, but it failed. A similar overture subsequently made to Athens met with better success, chiefly through an artifice of Alcibiades, who was at the head of a large party hostile to the peace, and the Athenians concluded a treaty offensive and defensive with Argos, Elis, and Mantinea for one hundred years (B.C. 420). In the year B.C. 418 the Argive confederacy was broken up by their defeat at the battle of Mantinea, and a peace, and soon after an alliance, was made between Sparta and Argos. In the year B.C. 416 an expedition was undertaken by the Athenians against Melos, which had hitherto remained neutral. The Melians surrendered at discretion; all the males who had attained manhood were put to death; the women and children were made slaves; and subsequently five hundred Athenian colonists were sent to occupy the island ( Thuc.v. 116).
The fifty years' peace was not considered at an end, though its terms had been broken on both sides, till the year B.C. 415, when the Athenians undertook their daring and tragic expedition to Sicily. (See Syracusae.) Sicily proved a rock against which their resources and efforts were fruitlessly expended. And Sparta, which furnished but a commander and a handful of men for the defence of Syracuse, soon beheld her antagonist reduced, by a series of unparalleled misfortunes, to a state of the utmost distress and weakness. The accustomed procrastination of the Spartans, and the timid policy to which they ever adhered, alone preserved Athens in this critical moment, or at least retarded her downfall. Time was allowed for her citizens to recover from the panic and consternation occasioned by the news of the Sicilian disaster; and instead of viewing hostile fleets, as they had anticipated, ravaging their coasts and blockading the Piraeus, they were enabled still to dispute the empire of the sea and to preserve the most valuable of their dependencies. Alcibiades, whose exile had proved so injurious to his country, since it was to his counsels alone that the successes of her enemies are to be attributed, now interposed in her behalf, and by his intrigues prevented the Persian satrap, Tissaphernes, from placing at the disposal of the Spartan admiral that superiority of force which must at once have terminated the war by the complete overthrow of the Athenian Republic ( Thuc.viii.). The temporary revolution which was effected at Athens by his contrivance also, and which placed the State at variance with the fleet and army stationed at Samos, afforded him another opportunity of rendering a real service to his country by moderating the violence and animosity of the latter. The victory of Cynossema and the subsequent successes of Alcibiades, now elected to the chief command of the forces of his country, once more restored Athens to the command of the sea, and, had she reposed that confidence in the talents of her generals which they deserved and her necessities required, the efforts of Sparta and the gold of Persia might have proved unavailing. But the second exile of Alcibiades, and, still more, the iniquitous sentence which condemned to death the generals who fought and conquered at Arginusae, sealed the fate of Athens; and the battle of Aegos Potamos at length terminated a contest which had been carried on, with scarcely any intermission, during a period of twenty-seven years, with a spirit and animosity unparalleled in the annals of warfare. Lysander now sailed to Athens, receiving as he went the submission of the allies, and blockaded the city, which surrendered after a few months (B.C. 404) on terms dictated by Sparta, with a view of making Athens a useful ally by giving the ascendency in the State to the oligarchical party.
The history of the Peloponnesian War was written by Thucydides, upon whose accuracy and impartiality, as far as his narrative goes, we may place the fullest dependence. His history ends [p. 1195] abruptly in the year B.C. 411. For the rest of the war we have to follow Xenophon and Diodorus. The value of Xenophon's history is impaired by his prejudice, and that of Diodorus by his carelessness. (Harpers Dictionary of Classical Antiquities, 1898)
A name given to the great contest between Athens and her allies on the one side, and the Peloponnesian confederacy, headed by Sparta, on the other, which lasted from B.C. 431 to 404. The war, which is one of the most memorable and epoch-making in the history of Europe, was a consequence of the jealousy with which Sparta and Athens regarded each other, as States each of which was aiming at supremacy in Greece, as the heads respectively of the Dorian and Ionian races, and as patrons of the two opposite forms of civil government, oligarchy and democracy. The war was eagerly desired by a strong party in each of those States, but it was necessary to find an occasion for commencing hostilities, especially as a truce for thirty years had been concluded between Athens and Sparta in the year B.C. 445. Such an occasion was presented by the affairs of Corcyra and Potidaea. In a quarrel, which soon became a war, between Corinth and Corcyra, respecting Epidamnus, a colony of the latter State (B.C. 436), the Corcyreans applied to Athens for assistance. Their request was granted, as far as the conclusion of a defensive alliance between Athens and Corcyra, and an Athenian fleet was sent to their aid, which, however, soon engaged in active hostilities against the Corinthians. Potidaea, on the isthmus of Pallené, was a Corinthian colony, and, even after its subjection to Athens, continued to receive every year from Corinth certain functionaries or officers (epidêmiourgoi). The Athenians, suspecting that the Potidaeans were inclined to join in a revolt, to which Perdiccas, king of Macedon, was instigating the towns of Chalcidicé, required them to dismiss the Corinthian functionaries, and to give other pledges of their fidelity. The Potidaeans refused, and, with most of the other Chalcidian towns, revolted from Athens and received aid from Corinth. The Athenians sent an expedition against them, and, after defeating them in battle, laid siege to Potidaea (B.C. 432). The Corinthians now obtained a meeting of the Peloponnesian confederacy at Sparta, in which they complained of the conduct of Athens with regard to Corcyra and Potidaea. After others of the allies had brought their charges against Athens, and after some of the Athenian envoys, who happened to be in the city, had defended the conduct of their State, the Spartans first, and afterwards all the allies, decided that Athens had broken the truce, and they resolved upon immediate war; King Archidamus alone recommended some delay.