Lysimachus had ruled Thrace for decades and parts of western Asia Minor ever since the Battle of Ipsus.

Seleucus ruled the Seleucid Empire, including lands currently covered by modern eastern Turkey, Syria, Lebanon, Israel, Iraq, and Iran.

After crossing the Hellespont to take possession of Lysimachus' European holdings not long after the battle, Seleucus was assassinated by Ptolemy Keraunos and Macedon swiftly became independent once again.

However, Lysimachus’ third and current wife, Arsinoe, wanted her children on the throne and so conspired with Ptolemy Keraunos to have Agathocles killed.

Agathocles’ widow and their children fled to Seleucus, giving him an opportunity to attack Lysimachus when he was weak, which he could not refuse.