By the event of the battle of Ipsus the allies, who had been united by their common enmity to Antigonus, were transformed into jealous rivals. Their struggle with him was no sooner decided, than the clashing interests of Ptolemy and Seleucus threatened an immediate rupture, which was averted indeed, but so as to leave neither party secure, and one of them deeply offended. It was clear that the possession of Syria must be a subject of perpetual contest between the two states. On the other hand, Lysimachus had reason to be satisfied–if it was in the nature of ambition to be so – with the rich acquisition which had fallen to his share: but he could feel no confidence in the moderation of his powerful neighbour, and might well suspect that Seleucus would endeavour to resume so important a concession on the first opportunity. In the eyes both of Lysimachus and Ptolemy, Seleucus had stept into the place of Antigonus; and they soon gave public proof of the jealousy with which they regarded him, by a new alliance which they contracted with one another. Lysimachus, although he had so lately married Amastris, and had children by a former wife, an Odrysian princess – among whom the eldest Agathocles was a youth of great promise – received the hand of Arsinoe, Ptolemy's daughter by Berenice.