Fifth Syrian War (202-195 BC)
The death of Ptolemy IV in 204 was followed by a bloody conflict over the regency as his heir, Ptolemy V, was just a child. The conflict began with the murder of the dead king's wife and sister Arsinoë by the ministers Agothocles and Sosibius. The fate of Sosibius is unclear, but Agothocles seems to have held the regency for some time until he was lynched by the volatile Alexandrian mob. The regency was passed from one adviser to another, and the kingdom was in a state of near anarchy.
Seeking to take advantage of this turmoil, Antiochus III staged a second invasion of Coele-Syria. He made an agreement with Philip V of Macedon to conquer and share the Ptolemies' overseas territories, although this greedy alliance did not last long. Antiochus quickly swept through the region. After a brief setback at Gaza, he delivered a crushing blow to the Ptolemies near the head of the River Jordan which earned him the important port of Sidon.
In 200 BC, Roman emissaries came to Philip and Antiochus demanding that they refrain from invading Egypt. The Romans would suffer no disruption of the import of grain from Egypt, key to supporting the massive population in Italy. As neither monarch had planned to invade Egypt itself, they willingly complied to Rome's demands. Antiochus completed the subjugation of Coele-Syria in 198 and went on to raid Ptolemy's remaining coastal strongholds in Caria and Cilicia.
Problems at home led Ptolemy to seek a quick and disadvantageous conclusion. The nativist movement, which began before the war with the Egyptian Revolt and expanded with the support of Egyptian priests, created turmoil and sedition throughout the kingdom. Economic troubles led the Ptolemaic government to increase taxation, which in turn fed the nationalist fire. In order to focus on the home front, Ptolemy signed a conciliatory treaty with Antiochus in 195, leaving the Seleucid king in possession of Coele-Syria and agreeing to marry Antiochus' daughter Cleopatra.
Syrian Wars - Wikipedia, the free encyclopedia