Aetolia is a mountainous region of Greece on the north coast of the Gulf of Corinth. The Achelous River separates Aetolia from Acarnania to the west; on the north it had boundaries with Epirus and Thessaly; on the east with the Ozolian Locrians; and on the south the entrance to the Corinthian Gulf defined the limits of Aetolia. Other Greeks considered Aetolians semi-barbaric, warlike and predatory. They worshiped Athena, not as goddess of wisdom, but as a goddess of war, and worshiped Apollo and Artemis as "Laphrios gods," patrons of the spoils and loot of war. They also worshiped Hercules, the river Achelous and Bacchus. To oppose Macedon and the Achaean League, they united under the Aetolian League, an effective political and administrative structure with a powerful army. By the end of the 3rd century B.C., the Aetolian League controlled the whole of central Greece outside Attica. At its height, the league included Locris, Malis, Dolopes, part of Thessaly, Phocis, and Acarnania. Some Mediterranean city-states, such as Kydonia on Crete, joined. As the first Greek ally of the Roman Republic, the league helped defeat Philip V of Macedon. Roman meddling in Greek affairs shifted opinion and a few years later the league sided with Antiochus III, the anti-Roman Seleucid king. Antiochus' defeat in 189 B.C. forced the league to sign a treaty that allowed it to exist but made it an feeble pawn of the Roman Republic.