Demetrius in Harpers Dictionary of Classical AntiquitiesA son of Antigonus and Stratonicé, surnamed Poliorcetes (Πολιορκητής), "besieger of cities," from his talents as an engineer and his peculiar skill in conducting sieges, especially by the aid of machines and engines either invented or improved by himself. At the age of twenty-two he was sent by his father against Ptolemy (B.C. 312), who had invaded Syria. He was defeated near Gaza, but soon repaired his loss by a victory over one of the generals of the enemy. He afterwards sailed with a fleet of 250 ships to Athens, and restored the Athenians to liberty, by freeing them from the power of Cassander and Ptolemy and expelling the garrison which was stationed there under Demetrius Phalereus. The gratitude of the Athenians to their deliverer passed all bounds, but Demetrius was soon summoned by his father to leave the flattery of their orators in order to resume the combined duties of an admiral and an engineer in the reduction of Cyprus. After a slight engagement with Menelaüs, the brother of Ptolemy, he laid siege to Salamis, the ancient capital of that island. The occurrences of this siege occupy a prominent place in history, not so much on account of the determined resistance opposed to the assailants and the great importance attached to its issue by the heads of the belligerent parties, as for a new species of warlike engine invented by Demetrius, and first employed by him against the city of Salamis. The instrument in question was called an ἑλέπολις, or "town-taker," and was an immense tower, consisting of nine stories, gradually diminishing as they rose in altitude, and affording accommodation for a large number of armed men, who thence discharged all sorts of missiles against the ramparts of the enemy. Ptolemy, dreading the fall of Salamis, which would pave the way, as he easily foresaw, for the entire conquest of Cyprus, had already made formidable preparations for compelling Demetrius to raise the siege. A memorable sea-fight ensued, in which the ruler of Egypt was completely defeated, with the loss of nearly all his fleet and 30,000 prisoners. An invasion of Egypt by Antigonus then took place, but ended disgracefully; and Demetrius was sent to reduce the Rhodians, who persisted in remaining allies of Ptolemy. The operations of Demetrius before Rhodes, and the resolute defence of the place by the inhabitants, present perhaps the most remarkable example of skill and heroism that is to be found in the annals of ancient warfare. The ἑλέπολις employed on this occasion greatly exceeded the one that was used in the siege of Salamis. Its towers were 150 feet high; it was supported on eight enormous wheels, and propelled by the labour of 3400 men. After a siege of a whole year, however, the enterprise was abandoned, a treaty was concluded with the Rhodians, and Demetrius, at the request of the Athenians, who were now again subjected to the Macedonians, proceeded to rescue Greece from the power of Cassander. In this he was so successful that he ultimately spread the terror of his arms over the whole of that country. The object of Antigonus and his son was now to effect the final subjugation of Macedonia, Egypt, and the East. The confederacy of Seleucus, Ptolemy, Lysimachus, and Cassander was therefore renewed, with the view of crushing these ambitious schemes, and in the battle of Ipsus they succeeded in effecting their object. Antigonus fell in the conflict, and Demetrius, after a precipitate flight of 200 miles, regained his fleet with only a small remnant of his once powerful host. Sailing soon after to Athens, he received information from the fickle inhabitants that they had resolved to admit no king within their city; upon which, finding that all Greece had now submitted to the influence of Cassander, he made a descent on the coast at Corinth for the mere purpose of plunder and revenge, and afterwards committed similar ravages along the whole coast of Thrace. Fortune, however, soon smiled again. Seleucus, jealous of the power of Lysimachus, whose territories now extended to the Syrian borders, resolved to strengthen his own dominions by forming an alliance with the family of Demetrius, which was still possessed of considerable claims and interests. He therefore made proposals for, and obtained in marriage, Stratonicé, the daughter of his former rival. The power of Demetrius again became formidable, an alliance with Ptolemy, who gave him his daughter Ptolemaïs in marriage, having also added to its increase. He compelled the Athenians to open their gates and receive a garrison; and having generously forgiven their previous fickleness, he turned his attention to Macedonia, and embracing an opportunity of interfering in the affairs of that country, which was afforded by dissensions between the two sons of Cassander, he cut off Alexander, one of the two princes, and made himself master of the throne. His restless ambition now projected new conquests in Europe and Asia. Turning his arms against Pyrrhus, he drove him from Thessaly, and then marched to Thebes, which he took by assault. About the same time also he built the city of Demetrias on the Pagasaean Gulf; and, in order to increase his naval power, formed a matrimonial union with the daughter of Agathocles, tyrant of Sicily. His fleet at length amounted to 500 galleys; while his land forces exceeded considerably 100,000 men, of which more than 12,000 were cavalry. This formidable power excited the alarm of Lysimachus and Ptolemy; the latter advanced against Greece with his fleet, while the former, with Pyrrhus his ally, made a land attack on Macedon in two different points at once. Demetrius took the field with his usual alacrity, but when he approached the position of Pyrrhus the greater part of his troops deserted him and he was compelled to flee. Leaving Macedon a prey to Lysimachus and Pyrrhus, Demetrius passed over into Asia Minor with a body of his best troops, resolved to assail his adversary in the most vulnerable quarter. The enterprise was at first attended with the most brilliant success. In a short time, however, a check was imposed on his career by Agathocles, the son of Lysimachus, and Demetrius was compelled to apply for protection to his aged son-in-law Seleucus. The latter yielded to his solicitations only so far as to grant him permission to spend two months within his territory; and was subsequently induced by his courtiers to rid himself of so dangerous a guest, by sending him a prisoner to a strong fortress on the Syrian coast, about sixty miles south of A sufficient revenue was allowed him for his support, and he was permitted to indulge in the chase and other exercises, always, however, under the eye of his keepers. At last, giving up all active pursuits, he died (B.C. 283) at the end of three years. The age of Demetrius at the time of his death was fifty-four. His posterity enjoyed the throne of Macedon in continued succession down to Perses, when the Roman conquest took place. See the life of Demetrius by Plutarch.
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