After the Second Macedonian War, the Italian League hoped that Rome would destroy Macedonia and kill or capture Philip V. Their purpose was to serve their own interests by exploiting the power vacuum that would be created in Greece in the absence of Macedonia. But Flamininus left Macedonia in the status quo. Not only that, he made strenuous efforts to bring peace to Greece and withdrew the Roman army from Greece as part of it.
The situation was not good for the Italian League, so they speculated about a dispute with Rome over the Syrian Seleucid emperor Antiochus III.
Meanwhile, in 196 BC, Antiochus conquered the lower part of Syria.In his eyes, the dream was to bring back the glory of the Seleucid Empire by occupying Asia Minor and Thrace. In 196 BC, he embarked on the expedition to Thrace. Meanwhile, his court proceedings with the Roman Senate continued. There was a consensus among them that Antiochus should limit its territory to Asia Minor and not extend its hand to Europe.
*Antiochus in Greece
Meanwhile, in 192 BC, the Italian League captured the city of Demetrius in Thessaly, asking Antiochus to come to Greece and mediate between Rome and them. Antiochus arrived in Greece with 100 ships and about 10,000 troops. He was accompanied by Hannibal, a one-time Nemesis of Rome.From Carthage he was working in exile Hannibal as a war adviser to Antiochus in the conspiracy of the enemy. The Roman Senate, meanwhile, was closely monitoring the situation in Greece. They sent an army of 25,000 troops to Apollonia.
Hannibal advised Antiochus to attack Italy directly. But Antiochus was aware of his limitations. He did not have the ability to cross the sea with a sufficient number of troops to attack Italy. Instead, he dominated Thessaly, Botia and Eboa, jointly with the Italian League. So at the end of 192 BC, Rome declared war on him.With the overall command of Greece, Consul Glabrio landed at the Iliarium. With him 10,000 infantry and 400 cavalry. Here he was joined by the armies of allied Macedonia and the Akyিয়ানn League. Glabrio recaptured all the territories occupied by Antiochus.
*Battle of Thermopylae (191 BC)
The combined Roman army consisted of about 33,000 warriors. In comparison, Antiochus has only 10,000 troops. The Italian League, meanwhile, was busy thwarting an attack by Roman allies in their territory, which was able to send only 4,000 troops.
Antiochus retreated to Thermopylae and pitched his tent.It was on this famous pass that a small number of Greek warriors, led by the Spartan emperor Leonidas, kept the Persian army at bay for a long time, allowing other Greek troops to retreat safely. Antiochus decided to confront the Romans here as it was not possible for a large army to come through this narrow pass at once.He sent some troops to take up positions at all the roads crossing the Thermopyly over the mountains, so that the Roman troops could not attack them from behind.