Battle of Ipsus
In the Wars of the Diadochi following Alexander's death, Coele-Syria initially came under the rule of Antigonus I Monophthalmus. In 301 BC Ptolemy I Soter, who four years earlier had crowned himself King of Egypt, exploited events surrounding the Battle of Ipsus to take control of the region. The victors at Ipsus, however, had allocated Coele-Syria to Ptolemy's former ally Seleucus I Nicator, founder of the Seleucid Empire. Seleucus, who had been aided by Ptolemy during his ascent to power, did not take any military action to reclaim the region. Once both were dead, however, their successors became embroiled in war.