The Aetolian League was an alliance of several Aitolian cities against the Spartans. It was centered in Aitolia, a mostly insignificant region of Greece at the time. Founded in the 370s BC, the league became a factor of power almost a century later, when the Aetolians stopped the Celtic invasion of Greece. This saved the Oracle of Delphi (279 BC). To commemorate the events, an annual festival with music and sportive competitions was introduced, the so-called Soteria.
The coinage of the Aetolian League began around that time. The obverse of this stater depicts the head of god Apollo, who had his home in Delphi and made his prophecies there. The reverse shows Aitolos, who, as Greek mythology had it, won his father's throne in Elis after a contest against his two brothers in Olympia.