The Macedonians had just concluded the First Macedonian War and Philip, seeing his chance to defeat Rhodes, formed an alliance with Aetolian and Spartan pirates who began raiding Rhodian ships. Philip also formed an alliance with several important Cretan cities, such as Hierapynta and Olous. With the Rhodian fleet and economy suffering from the depredations of the pirates, Philip believed his chance to crush Rhodes was at hand. To help achieve his goal, he formed an alliance with the King of the Seleucid Empire, Antiochus the Great, against Ptolemy V of Egypt (the Seleucid Empire and Egypt were the other two Diadochi states). Philip began attacking the lands of Ptolemy and Rhodes's allies in Thrace and around the Sea of Marmara.