(Δημοσθένης), son of Alcisthenes, Athenian general, is one of the prominent characters of the Peloponnesian war. He was appointed in the sixth year, B. C. 426, to the command with Procles of a squadron of thirty ships sent on the annual cruise around Peloponnesus. Their first important efforts were directed against Leucas; and with the aid of a large force of Acarnanians, Zacynthians, Cephallenians, and Corcyraeans, it seemed highly probable that this important ally of Sparta might be reduced. And the Acarnanians were urgent for a blockade. Demosthenes, however, had conceived, from the information of the Messenians, hopes of a loftier kind ; and, at the risk of offending the Acarnanians, who presently declined to co-operate, sailed with these views to Naupactus. The Corcyraeans had also left hin, but he still persevered in his project, which was the reduction of the Aetolians,--an operation which, once effected, would open the way to the Phocians, a people ever well disposed to Athens, and so into Boeotia. It was not too much to hope that northern Greece might thus be wholly detached from the Spartan alliance, and the war be made strictly Peloponnesian. The success of the first move in this plan depended much on the aid of certain allies among the Ozolian Locrians, who were used to the peculiar warfare of the enemy. These, however, were remiss, and Demosthenes, fearing that the rumour of his purpose would rouse the whole Aetolian nation, advanced without them. His fear had been already realized, and as soon as the resources of his archery were exhausted, he was obliged to retreat, and this retreat the loss of his guide rendered even more disastrous than might have been expected for a force of heavy-armed men amidst the perpetual assaults of numerous light armed enemies. " There was every kind of flight and destruction," says Thucydides, " and of 300 Athenians there fell 120, a loss rendered heavy beyond proportion, through the peculiar excellence of this particular detachment." (Thuc. 3.91, 94, 98; Diod. 12.60.)

This, however, seemed to be hardly the worst consequence. The Aetolians sent ambassadors to Sparta, to ask for aid to reduce Naupactus; and received under the command of Eurylochus 3000 men-at-arms. The Ozolian Locrians were overawed into decided alliance. But Naupactus Demosthenes was enabled to save by reinforcements obtained on urgent entreaty from the offended Acarnanians ; and Eurylochus led off his forces for the present to Calydon, Pleuron, and Proschium. Yet this was but the preliminary of a more important movement. The Ambraciots, on a secret understanding with him, advanced with a large force into the country of their ancient enemy, the Amphilochian Argos; they posted themselves not far from the town, at Olpae. Eurylochus now broke up, and, by a judicious route, passing between the town itself and Crenae, where the Acarnanians had assembled to intercept him, effected a junction with these allies. Presently, on the other hand, Demosthenes arrived with twenty ships, and under his conduct the final engagement took place at Olpae, and was decided, by an ambuscade which he planted, in favour of the Athenians and Acarnanians. An almost greater advantage was gained by the compact entered into with Menedaeus, the surviving Spartan officer, for the underhand withdrawal of the Peloponnesians. And, finally, haying heard that the whole remaining force of Ambracia was advancing in support, he succeeded further in waylaying and almost exterminating it in the battle of Idomene. The Athenians received a third part of the spoils, and the amount may be estimated from the fact, that the share of Demosthenes, the only portion that reached Athens in safety, was no less than 300 panoplies. (Thuc. 3.102, 105_114; Diod. 12.60.)

Demosthenes might now safely venture home : and in the next year he was allowed, at his own request, though not in office, to accompany Eurymedon and Sophocles, the commanders of a squadron destined for Sicily, and empowered to use their services for any object he chose on the Peloponnesian coast. They, however, would not hear of any delay, and it was only by the chance of stress of weather, which detained the fleet at Pylos, his choice for his new design, that he was enabled to effect his purpose. The men themselves while waiting, took the fancy to build him his fort; and in it he was left with five ships. Here he was assailed by the Lacedaemonians, whom the news had recalled out of Attica, and from Corcyra, and here with great spirit and success he defeated their attempt to carry the place on the sea side. The arrival of forty Athenian ships, for which he had sent, and their success in making their way into the harbour, reversed his position. The Lacedaemonians, who in their siege of the place had occupied the neighbouring island, were now cut off and blockaded, and Sparta now humbled herself to ask for peace. The arrogance of the people blighted this promise ; and as the winter approached it became a question whether the whole advantage was not likely to be lost by the escape of the party. Demosthenes, however, was devising an expedient, when joined or rather, in fact, superseded by Cleon [CLEON], who nevertheless was shrewd enough not to interfere, possibly had even had intimation of it throughout. His Aetolian disaster had taught him the value of light and the weakness of heavy arms. Landing at two points with a force of which one-third only were full-armed, by a judicious distribution of his troops, and chiefly by the aid of his archers and targeteers. he effected the achievement, then almost incredible, of forcing the Spartans to lay down their arms. (Thuc. 4.2_40; Diod. 12.61-63.)

The glory of this success was with the vulgar given to Cleon, yet Demosthenes must have surely had some proportion of it. He was probably henceforth in general esteem, as in the Knights of Aristophanes, coupled at the head of the list of the city's generals with the high-born and influential Nicias. We find him in the following year (B. C. 424) commanding with Hippocrates in the operation in the Megarid; possessing himself by a stratagem of the Long Walls uniting Megara to Nisaea, and receiving shortly the submission of Nisaea itself, though baffled by the advance of Brasidas in the main design on Megara. Soon after, he concerted with the same colleague a grand attempt on Boeotia. On a fixed day Hippocrates was to lead the whole Athenian force into the south-eastern frontier, and occupy Delium, while Demosthenes was to land at Siphae, and by the aid of the democratic party, possess himself of it and of Chaeroneia. Demosthenes with this view took forty ships to Naupactus, and, having raised forces in Acarnania, sailed for Siphae. But either he or Hippocrates had mistaken the day; his arrival was too early, and the Boeotians, who had moreover received information of the plot, were enabled to bring their whole force against Demosthenes, and yet be in time to meet his colleague at Delium. The whole design was thus overthrown, and Demosthenes was further disgraced by a repulse in a descent on the territory of Sicyon. (Thuc. 4.66_74, 76, 77, 89, 101; Diod. 12.66-69.)

He does not reappear in history, except among the signatures to the treaties of the tenth year, B. C. 422 (Thuc. 5.19, 24), till the nineteenth, B. C. 413. On the arrival of the despatch from Nicias giving an account of the relief of Syracuse by Gylippus, he was appointed with Eurymedon to the command of the reinforcements, and, while the latter went at once to Sicily, he remained at home making the needful preparations. Early in the spring he set sail with sixty-five ships; and after some delays, how far avoidable we cannot say, at Aegina and Corcyra, on the coasts of Peloponnesus and of Italy, reached Syracuse a little too late to prevent the first naval victory of the besieged. (Thuc. 7.16, 17, 20, 26, 31, 33, 35, 42.)

The details of this concluding portion of the Syracusan expedition cannot be given in a life of Demosthenes. His advice, on his arrival, was to make at once the utmost use of their own present strength and their enemies' consternation, and then at once, if they failed, to return. No immediate conclusion of the siege could be expected without the recovery of the high ground commanding the city, Epipolae. After some unsuccessful attempts by day, Demosthenes devised and put into effect a plan for an attack, with the whole forces, by night. It was at first signally successful, but the tide was turned by the resistance of a body of Boeotians, and the victory changed to a disastrous defeat. Demosthenes now counselled an immediate departure, either to Athens, or, if Nicias, whose professions of greater acquaintance with the internal state of the besieged greatly influenced his brother generals, really had grounds for hope, at any rate from their present unhealthy position to the safe and wholesome situation of Thapsus. Demosthenes reasoned in vain: then ensued the fatal delay, the return of Gylippus with fresh reinforcements, the late consent of Nicias to depart, and the infatuated recal of it on the eclipse of the moon, the first defeat and the second of the all-important ships. In the latter engagement Demosthenes had the chief command, and retained even in the hour of disaster sufficient coolness to see that the only course remaining was at once to make a fresh attempt to break through the blockading ships and force their way to sea. And he had now the voice of Nicias with him : the army itself in desperation refused. In the subsequent retreat by the land, Demosthenes for some time is described simply as cooperating with Nicias, though with the separate command of the second and rearward division. This, on the sixth day, through its greater exposure to the enemy, was unable to keep up with the other; and Demosthenes, as in his position was natural, looked more to defence against the enemy, while Nicias thought only of speedy retreat. The consequence was that, having fallen about five miles and a half behind, he was surrounded and driven into a plot of ground planted with olives, fenced nearly round with a wall, where he was exposed to the missiles of the enemy. Here he surrendered, towards evening, on condition of the lives of his soldiers being spared.

His own was not. In confinement at Syracuse Nicias and he were once more united, and were together relieved by a speedy death. Such was the unworthy decree of the Syracusan assembly, against the voice, say Diodorus and Plutarch, of Hermocrates, and contrary, says Thucydides, to the wish of Gylippus, who coveted the glory of conveying the two great Athenian commanders to Sparta. (Thuc. 7.42_87; Diod. 13.10_33; Plut. Nicias, 20-28.) Timaeus, adds Plutarch, related that Hermocrates contrived to apprize them of the decree, and that they fell by their own hands. Demosthenes may be characterized as an unfortunate general. Had his fortune but equalled his ability, he had achieved perhaps a name greater than any of the generals of his time. In the largeness and boldness of his designs, the quickness and justice of his insight, he rises high above all his contemporaries. In Aetolia the crudeness of his first essay was cruelly punished; in Acarnania and at Pylos, though his projects were even favoured by chance, yet the proper result of the one in the reduction of Ambracia was prevented by the jealousy of his allies; and in the other his own individual glory was stolen by the shameless Cleon. In the designs against Megara and Boeotia failure again attended him. In his conduct of the second Syracusan expedition there is hardly one step which we can blame: with the exception of the night attack on Epipolae, it is in fact a painful exhibition of a defeat step by step effected over reason and wisdom by folly and infatuation. It is possible that with the other elements of a great general he did not combine in a high degree that essential requisite of moral firmness and command: he may too have been less accurate in attending to the details of execution than he was farsighted and fertile in devising the outline. Yet this must be doubtful: what we learn from history is, that to Demosthenes his country owed her superiority at the peace of Nicias, and to any rather than to him her defeat at Syracuse. Of his position at home among the various parties of the state we know little or nothing: he appears to have been of high rank: in Aristophanes he is described as leading the charge of the Hippeis upon Cleon (Equites, 242), and his place in the play throughout seems to imply it.