Social War (220–217 BC)

The Social War, also War of the Allies and the Aetolian War, was fought from 220 BC to 217 BC between the Hellenic League under Philip V of Macedon and the Aetolian League, Sparta and Elis. It was ended with the Peace of Naupactus.

Many of the tensions which led to the war were later documented by the Greek historian, Polybius.

The end of the "War of Demetrius,” also called the First Illyrian War, in 228 left the Aetolian League greater in size than ever before. They worked to continue to expand in all directions. Their attempt to expand into Thessaly, where Macedon had recently collapsed, resulted in a violent reaction from Macedon, the first in almost four decades. This created an unceasing suspicion between the two for years to come.

A new alliance emerged among Macedon, the Kingdom of Epirus, the Boeotian League, and the Achaean League in the mid 220s, which gave much power and near total control of all Greece to Macedon and the Hellenic League. The Aetolian League began taking defensive measures, being nearly completely encircled by the members of the Hellenic League, or symmachy. Since 229, Antigonus Doson had been guardian and king of Macedon, because the military felt that Philip, the rightful heir, was too young to be an effective ruler.Philip V would begin coming to power as these new areas were entering the Hellenic League.

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