(Δημήτριος) II., king of SYRIA, surnamed NICATOR (Νικάτωρ), was the son of Demetrius Soter. He had been sent by his father for safety to Cnidus, when Alexander Balas invaded Syria, and thus escaped falling into the hands of that usurper. After the death of his father he continued in exile for some years; but the vicious and feeble character of Balas having rendered him generally odious to his subjects, Demetrius determined to attempt the recovery of his kingdom, and assembled a body of mercenaries from Crete, with which he landed in Cilicia, B. C. 148 or 147. Ptolemy Philometor, who was at the time in the southern provinces of Syria with an army, immediately declared in his favour, and agreed to give him his daughter Cleopatra, who had been previously married to the usurper Balas, for his wife. With their combined forces they took possession of Antioch, and Alexander, who had retired to Cilicia, having returned to attack them, was totally defeated at the river Oenoparas. Ptolemy died of the injuries received in the battle, and Balas, having fled for refuge to Abae in Arabia, was murdered by his followers. (Just. 35.2; Liv. Epit. Iii.; Diod. Exc. Photii, xxxii.; Appian, App. Syr. 67; J. AJ 13.4; 1 Macc. x. xi.) For this victory Demetrius obtained the title of Nicator; and now deeming himself secure both from Egypt and the usurper, he abandoned himself to the grossest vices, and by his excessive cruelties alienated the minds of his subjects, at the same time that he estranged the soldiery by dismissing all his troops except a body of Cretan mercenaries. This conduct emboldened one Diodotus, surnamed Tryphon, to set up Antiochus, the infant son of Alexander Balas, as a pretender against him. Tryphon obtained the powerful support of Jonathan Maccabaeus, and succeeded in establishing his power firmly in a great part of Syria, and even in making himself master of Antioch. Demetrius, whether despairing of recovering these provinces, or desirous of collecting larger forces to enable him to do so, retired to Seleucia and Babylon, and from thence was led to engage in an expedition against the Parthians, in which, after various successes, he was defeated by stratagem, his whole army destroyed, and he himself taken prisoner, B. C. 138. (Justin, 36.1, 38.9; Liv. Epit. Iii.; Appian, App. Syr. 67; Joseph. Ant. xiii 5; 1 Macc. xi. xiv.)
According to Appian and Justin it would appear that the revolt of Tryphon did not take place till after the captivity of Demetrius, but the true sequence of events is undoubtedly that given in the book of the Maccabees. He was, however, kindly treated by the Parthian king Mithridates (Arsaces VI.), who though he sent him into Hyrcania, allowed him to live there in regal splendour, and even gave him his daughter Rhodogune in marriage. After the death of Mithridates he made various attempts to escape, but notwithstanding these was still liberally treated by Phraates, the successor of Mithridates. Meanwhile his brother, Antiochus Sidetes, having overthrown the usurper Tryphon and firmly established himself on the throne, engaged in war with Parthia, in consequence of which Phraates brought forward Demetrius, and sent him into Syria to operate a diversion against his brother. This succeeded better than the Parthian king had anticipated, and Antiochus having fallen in battle, Demetrius was able to reestablish himself on the throne of Syria, after a captivity of ten years, and to maintain himself there in spite of Phraates, B. C. 128. (Justin, 38.9, 10; Euseb. Arm. p. 167; J. AJ 13.8.4.) He even deemed himself strong enough to engage in an expedition against Egypt, but was compelled to abandon it by the general disaffection both of his soldiers and subjects. Ptolemy Physcon took advantage of this to set up against him the pretender Alexander Zebina, by whom he was defeated and compelled to fly. His wife Cleopatra, who could not forgive him his marriage with Rhodogune in Parthia, refused to afford him refuge at Ptolemais, and he fled to Tyre, where he was assassinated while endeavouring to make his escape by sea, B. C. 125. (Justin, 39.1; J. AJ 13.9.3, Euseb. Arm. p.168; Clinton, F. H. iii. pp. 333-5.) According to Appian (App. Syr. 68) and Livy (Epit. lx.), he was puttodeath by his wife Cleopatra. He left two sons, Seleucus, who was assassinated by order of Cleopatra, and Antiochus, surnamed