(Ἀντίγονος), king of ASIA, surnamed the One-eyed (Lucian, Macrob. 11; Plut. de Pueror. Educ. 14), was the son of Philip of Elymiotis. He was born about B. C. 382, and was one of the generals of Alexander the Great, and in the division of the empire after his death (B. C. 323), he received the provinces of the Greater Phrygia, Lycia, and Pamphylia. Perdiccas, who had been appointed regent, had formed the plan of obtaining the sovereignty of the whole of Alexander's dominions, and therefore resolved upon the ruin of Antigonus, who was likely to stand in the way of his ambitious projects. Perceiving the danger which threatened him, Antigonus fled with his son Demetrius to Antipater in Macedonia (321); but the death of Perdiccas in Egypt in the same year put an end to the apprehensions of Antigonus. Antipater was now declared regent; he restored to Antigonus his former provinces with the addition of Susiana, and gave him the commission of carrying on the war against Eumenes, who would not submit to the authority of the new regent. In this war Antigonus was completely successful; he defeated Eumenes, and compelled him to take refuge with a small body of troops in Nora, an impregnable fortress on the confines of Lycaonia and Cappadocia; and after leaving this place closely invested, he marched into Pisidia, and conquered Alcetas and Attalus, the only generals who still held out against Antipater (B. C. 320). [ALCETAS.]

The death of Antipater in the following year (B. C. 319) was favourable to the ambitious views of Antigonus, and almost placed within his reach the throne of Asia. Antipater had appointed Polysperchon regent, to the exclusion of his own son Cassander, who was dissatisfied with the arrangement of his father, and claimed the regency for himself. He was supported by Antigonus, and their confederacy was soon afterwards joined by Ptolemy. But they found a formidable rival in Eumenes, who was appointed by Polysperchon to the command of the troops in Asia. Antigonus commanded the troops of the confederates, and the struggle between him and Eumenes lasted for two years. The scene of the first campaign (B. C. 318) was Asia Minor and Syria, of the second (B. C. 317) Persia and Media. The contest was at length terminated by a battle in Gabiene at the beginning of B. C. 316, in which Eumenes was defeated. He was surrendered to Antigonus the next day through the treachery of the Argyraspids, and was put to death by the conqueror.

Antigonus was now by far the most powerful of Alexander's generals, and was by no means disposed to share with his allies the fruits of his victory. He began to dispose of the provinces as he thought fit. He caused Pithon, a general of great influence, to be brought before his council, and condemned to death on the charge of treachery, and executed several other officers who shewed symptoms of discontent. After taking possession of the immense treasures collected at Ecbatana and Susa, he proceeded to Babylon, where he called upon Seleucus to account for the administration of the revenues of this province. Such an account, however, Seleucus refused to give, maintaining that he had received the province as a free gift from Alexander's army; but, admonished by the recent fate of Pithon, he thought it more prudent to get out of the reach of Antigonus, and accordingly left Babylon secretly with a few horsemen, and fled to Egypt.

The ambitious projects and great power of Antigonus now led to a general coalition against him, consisting of Seleucus, Ptolemy, Cassander, and Lysimachus. The war began in the year 315, and was carried on with great vehemence and alternate success in Syria, Phoenicia, Asia Minor, and Greece. After four years, all parties became exhausted with the struggle, and peace was accordingly made, in B. C. 311, on condition that the Greek cities should be free, that Cassander should retain his authority in Europe till Alexander Aegus came of age, that Lysimachus and Ptolemy should keep possession of Thrace and Egypt respectively, and that Antigonus should have the government of all Asia. The name of Seleucus, strangely enough, does not appear in the treaty.

This peace, however, did not last more than a year. Ptolemy was the first to break it, under pretence that Antigonus had not restored to liberty the Greek cities in Asia Minor, and accordingly sent a fleet to Cilicia to dislodge the garrisons of Antigonus from the maritime towns. (B. C. 310.) Ptolemy was at first successful, but was soon deprived of all he had gained by the conquests of Demetrius (Poliorcetes), the son of Antigonus. Meanwhile, however, the whole of Greece was in the power of Cassander, and Demetrius was therefore sent with a large fleet to effect a diversion in his father's favour. Demetrius met with little opposition ; he took possession of Athens in B. C. 307, where he was received with the most extravagant flattery. He also obtained possession of Megara, and would probably have become master of the whole of Greece, if he had not been recalled by his father to oppose Ptolemy, who had gained the island of Cyprus. The fleet of Demetrius met that of Ptolemy off the city of Salamis in Cyprus, and a battle ensued, which is one of the most memorable of the naval engagements of antiquity. Ptolemy was entirely defeated (B. C. 306), and Antigonus assumed in consequence the title of king, and the diadem, the symbol of royal power in Persia. He also conferred the same title upon Demetrius, between whom and his father the most cordial friendship and unanimity always prevailed. The example of Antigonus was followed by Ptolemy, Lysimachus, and Seleucus, who are from this time designated as kings. The city of Antigoneia on the Orontes in Syria was founded by Antigonus in the preceding year (B. C. 307).

Antigonus thought that the time had now come for crushing Ptolemy. He accordingly invaded Egypt with a large force, but his invasion was as unsuccessful as Cassander's had been : he was obliged to retire with great loss. (B. C. 306.) He next sent Demetrius to besiege Rhodes, which had refused to assist him against Ptolemy, and had hitherto remained neutral. Although Demetrius made the most extraordinary efforts to reduce the place, he was completely baffled by the energy and perseverance of the besieged; and was therefore glad, at the end of a year's siege, to make peace with the Rhodians on terms very favourable to the latter. (B. C. 304.) While Demetrius was engaged against Rhodes, Cassander had recovered his former power in Greece, and this was one reason that made Antigonus anxious that his son should make peace with the Rhodians. Demetrius crossed over into Greece, and after gaining possession of the principal cities without much difficulty, collected an assembly of deputies at Corinth (B. C. 303), which conferred upon him the same title that had formerly been bestowed upon Philip and Alexander. He now prepared to march northwards against Cassander, who, alarmed at his dangerous position, sent proposals of peace to Antigonus. The proud answer was, " Cassander must yield to the pleasure of Antigonus." But Cassander had not sunk so low as this: he sent ambassadors to Seleucus and Ptolemy for assistance, and induced Lysimachus to invade Asia Minor in order to make an immediate diversion in his favour. Antigonus proceeded in person to oppose Lysimachus, and endeavoured to force him to an engagement before the arrival of Seleucus from upper Asia. But in this he could not succeed, and the campaign accordingly passed away without a battle. (B. C. 302.) During the winter, Seleucus joined Lysimachus, and Demetrius came from Greece to the assistance of his father. The decisive battle took place in the following year (B. C. 301), near Ipsus in Phrygia. Antigonus fell in the battle, in the eighty-first year of his age, and his army was completely defeated. Demetrius escaped, but was unable to restore the fortunes of his house. [DEMETRIUS.] The dominions of Antigonus were divided between the conquerors : Lysimachus obtained the greater part of Asia Minor, and Seleucus the countries between the coast of Syria and the Euphrates, together with a part of Phrygia and Cappadocia. (Diod. lib. xviii.-xx. ; Plut. Eumenes and Demetrius ; Droysen, Geschichte der Nachfolger Alexanders ; Thirlwall's Greece, vol. vii.)

The head on the following coin of Antigonus, Fröhlich supposes to be Neptune's, but Eckhel thinks that it represents Dionysus, and that the coin was struck by Antigonus after his naval victory off Cyprus, in order to shew that he should subdue all his enemies, as Dionysus had conquered his in India. (Eckhel, vol. ii. p. 118.)