The late conquests of his father in Asia Minor entangled Antiochus in new wars; although, by the marriage of his stepdaughter Phila with Antigonus Gonatas, he ceded his claims on Macedonia, 277.--Fruitless attempt at subjecting Bithynia, 279; the king of that country, Nicomedes, calls in the Gauls, who had invaded Macedonia, and gives them a settlement in Galatia, 277, where they keep their footing, even after the victory won over them by Antiochus, 275, and by their participation in the wars, as mercenaries, become of importance.--The newly risen state of Pergamus likewise thrives, at the expense of the Syrian empire, in spite of Antiochus's attack, 263; and the inroad into Egypt, for the purpose of supporting the rebel Magas, is anticipated by Ptolemy II. 264. 10. Antiochus II. surnamed [Greek: Theos]. During his reign the sway was in the hands of women; and the diseased state of the interior of the empire became palpable by the secession of various eastern provinces, out of which arose the Parthian and Bactrian kingdoms. The boundless luxury of the court hurried on the decline of the ruling family; having once begun to sink, it could not without difficulty have retrieved its virtue independently of the matrimonial connections now constantly formed from within itself. Ascendancy of his stepsister and wife Laodice, and of his sister Apame, relict of Magas; the latter involves him in war with Ptolemy II. to vindicate her claims upon Cyrene; it ends by Antiochus's marriage with Berenice, daughter of Ptolemy, and his repudiation of Laodice, 260-252. Having, after the death of Ptolemy, 247, put away Berenice and taken back Laodice; the latter, distrusting his motives, cuts him off by poison.--The secession of Parthia happened in consequence of the expulsion of the Macedonian governor by Arsaces, founder of the house of the Arsacidae: that of Bactria, on the other hand, was brought about by the Macedonian governor himself, Theodotus, who asserted his independence. (Concerning these two kingdoms, see below, book iv. period iii. Dist. Kingdoms iv. parag. 4, 5.) At first, the former of these kingdoms comprised but a part of Parthia; the latter only Bactria, and, perhaps, Sogdiana; both, however, were soon enlarged at the expense of the Seleucidae. 11. Seleucus II. surnamed Callinicus. His reign, twenty years in duration, is one unbroken series of wars; in which the kingdom, already enfeebled, was subverted, partly by the struggle with Egypt, caused by the hatred between Laodice and Berenice; partly by the jealousy of his brother Antiochus Hierax; and partly by vain attempts at recovering the upper provinces.