In Syria, Antigonus had entrusted the supreme command against Ptolemy and Seleucus to his son Demetrius, who was then still a very young man. This Demetrius plays a very prominent part in history. He has the honour of having his life described among the biographies in Plutarch—an honour which we might reasonably grudge Demetrius, for he is a despicable person. We know him, partly from Plutarch’s biographies, and partly from a number of anecdotes in Athenæus, to have been the most unprincipled and most detestable man in existence: the acts of faithlessness which he committed against Alexander, the son of Cassander, are not the only things for which he deserves our detestation. He was also a voluptuary of the vulgarest and most abject description; the lowest crapule was the element in the filth of which he revelled; and he was quite a heartless man, who knew no friendship; the basest creatures, the companions of his lusts, were his only friends. Cassander was, after all, capable of distinguishing persons deserving of respect, as he showed in the selection of Demetrius Phalereus; and so also was Ptolemy; but we know that Demetrius Poliorcetes lived at Athens in intimacy with the most abject and abandoned persons of the time. He also showed towards his soldiers an ingratitude and a heartlessness, which are quite revolting; they were perfectly indifferent to him, and he regarded them only as his tools. They accomplished great things for him, but he always sacrificed them without any scruple, leaving to destruction on the morrow those who had saved his life the day before. In addition to this, he was a gambler, whose dull torpor could be excited only by great changes of fortune, and who staked everything upon a card. He is remarkable for his enormous good fortune: “fortune raised him beyond all conception, and then deserted him, but when he seemed entirely lost, she again held out her hand to him,” says Plutarch, in a verse which he applies to him.
Such a man would deserve no attention at all, were it not that he acted a great part, and that nature had endowed him with great abilities, especially in mechanics, according to the leaning of that age toward the mechanical sciences. In this respect, as in many others, we may compare him with a modern person, the regent Philip of Orleans, who, however, was a far better man. Demetrius was a great inventor in mechanics, and he did much for the improvement of military engineering: this is a merit which he did not unfairly assume, but he is fully entitled to his reputation in this respect. A short time before, a great impulse had been given to mechanics in the affairs of war, and machines of every description were improved. Engines, which for centuries had remained unchanged, were now, partly through the progress of mathematics, and partly through the increased wealth that could be employed upon them, improved in one year, more than they were formerly in the course of centuries.
Demetrius was eighteen years old when Antigonus commissioned him to undertake the command of an army against Ptolemy. The first attempt failed, for at Gaza he was completely defeated, and Ptolemy again took possession of Cœle-Syria. Ptolemy carried on the war in a generous spirit, for, declaring it to be a civil war between Macedonians, he set the prisoners free without ransom, whereby he gained the good will of the Macedonians. Antigonus now undertook the command himself, and Ptolemy again evacuating the towns of Cœle-Syria, ravaged them.
Peace was then concluded, but it lasted only for a short time. Cassander succeeded in inducing Ptolemy, the nephew of Antigonus, who was stationed in Bœotia, as well as another general on the Hellespont, to revolt. Yet Antigonus soon recovered those countries. In the same year Ptolemy took Cyprus and extended his power on the coast of Asia Minor.
In the year following Ptolemy appeared with a fleet in Greece, having until then been the ally of Cassander. It was probably the Bœotians and Peloponnesians that called in his assistance against Polysperchon, and he had a fair opportunity of being able to say that he was coming to avenge the murder of Roxane and Alexander. Cratesipolis surrendered to him her principality of Argos and Sicyon, being unable to maintain those cities any longer; but it was not without difficulty that the mercenaries were prevailed upon to surrender: it was effected only by stratagem. The Peloponnesians afterwards were slow in doing what they had promised, and Ptolemy himself probably did not care much about the conquest. Hence he concluded a treaty with Cassander, whereby he obtained possession of Peloponnesus with the exception of Argos and Sicyon.
[308-306 B.C.]
Antigonus now sent his son Demetrius with a fleet to Greece. No one there was willing to sacrifice himself for Cassander, who had no fleet, so that he was unable to undertake anything against Demetrius. The latter appeared unexpectedly before Piræus: the harbour not being closed, he landed and quickly took Piræus, before the posts could be occupied. He immediately proclaimed that the expedition had been undertaken for the purpose of restoring to Athens her freedom and autonomy, and he was accordingly received with enthusiasm. The Macedonian garrison under Dionysius shut itself up in Munychia, and negotiations were commenced between Demetrius Poliorcetes and the city. Demetrius Phalereus was sent as ambassador down to the camp in Piræus: Demetrius promised the Athenians an amnesty, the city was declared free, and the ancient democratic constitution was restored; but Demetrius Phalereus was sent into exile.
Demetrius Poliorcetes now besieged the Macedonians in Munychia. He would not go to Athens till he had taken that fortress; it was at first blockaded, while the preparations for a siege were going on. While the engines were building, Demetrius marched against Megara, where there was a garrison of Cassander. The town was taken by storm and plundered, and it was only at the urgent request of the Athenian ambassadors, that its inhabitants were saved and not dragged away into slavery. He then returned to Piræus, where he attacked Munychia, until the feeble garrison being exhausted, was obliged, after several days, to surrender, and then departed. The fortifications were razed to the ground, and the place given up to the Athenians. Athens was now free, but Demetrius, for the protection of the Athenians, gave them a garrison of his own troops. After this he stayed for a time at Athens, where he was received with enthusiasm, as elsewhere described.
If Demetrius had remained at Athens, and continued the war against Cassander, he might easily have conquered all Greece; but he was called away by his father Antigonus, because Ptolemy had made himself master of Cyprus. About the month of Hecatombæon, Demetrius sailed to Cyprus; and now, by a brilliant victory of Demetrius over Menelaus, the brother of Ptolemy, near Salamis in Cyprus, Antigonus and Demetrius gained the mastery at sea. Cyprus was reconquered. Menelaus, with all his forces in the island, was obliged to capitulate; and thus the sea far and wide was in the power of Antigonus and his son. But an expedition which the two undertook against Egypt proved a failure.