25. The real heir to the throne, Demetrius, being detained at Rome as an hostage, Epiphanes was first succeeded by his son Antiochus V. surnamed Eupator, a child nine years old. During his short reign, the quarrels of his guardians, the despotism of the Romans, the protracted war with the Jews, and the commencing conquests of the Parthians, reduced the kingdom of the Seleucidae to a powerless state. Contest between Lysias, regent in the absence of Epiphanes, and Philip, appointed by the king, previously to his death, as guardian of the young prince, terminated by the defeat of Philip, 162.--Eupator's right acknowledged at Rome, in order that the guardianship might fall into the hands of the senate, who administer the government by means of a commission sent over into Syria, and completely deprive the king of all power of resistance. Octavius, head of the commission, put to death, probably at the instigation of Lysias.--While the Parthian king, Mithridates I. is prosecuting his conquests at the expense of the Syrian kingdom in Upper Asia, Demetrius secretly escapes out of Rome, takes possession of the throne, and causes Eupator and Lysias to be put to death, 161. 26. Demetrius I. surnamed Soter. He succeeded in getting himself acknowledged at Rome, on which all now depended. The attempts to extend his power, by supporting Orofernes, the pretender to the crown of Cappadocia, against the king Ariarathes, had their origin partly in family relations, but still more, as was the case with almost all political transactions of those times, in bribery. By this act he only drew upon himself the enmity of the kings of Egypt and Pergamus; as, moreover, he was hated by his subjects on account of his intemperance, the chances of success were greatly in favour of the shameful usurpation of Alexander Balas, brought about by Heraclidas the expelled governor of Babylon, and backed by the yet more shameful conduct of the Roman senate, who acknowledged his title to the throne. The Syrian kingdom was now fallen so low, that both king and usurper were obliged to court the favour of the Jews under Jonathan, hitherto regarded as rebels. In the second battle Demetrius lost his life. 27. The usurper Alexander Balas endeavoured to confirm his power by a marriage with Cleopatra, daughter of Ptolemy Philometor: but he soon evinced himself more unworthy even than his predecessor of wielding the sceptre. While he abandoned the government to his favourite, the detested Ammonius, the eldest remaining son of Demetrius succeeds not only in raising a party against the usurper, but even in prevailing on Philometor to side with himself, and give him in marriage Cleopatra, whom he takes away from Balas. The consequence of this alliance with Egypt was the defeat and downfal of Balas, although it cost Philometor his life.