Aetolia was a region of ancient Greece.
The river Achelous 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.
In classical times Aetolia comprised two parts: Old Aetolia in the west, from the Achelous to the Evenus and Calydon; and New Aetolia or Acquired Aetolia in the east, from the Evenus and Calydon to the Ozolian Locrians. The country has a level and fruitful coastal region, but an unproductive and mountainous interior. The mountains contained many wild beasts, and acquired fame in Greek mythology as the scene of the hunt for the Calydonian Boar.
The peoples known as the Curetes and the Leleges originally inhabited the country, but at an early period Greeks from Elis, led by the mythical eponym Aetolus, set up colonies. The Aetolians took part in the Trojan War, under their king Thoas .
They continued for a long time a rude and uncivilized people, living to a great extent by robbery; and even in the time of Thucydides (410 BC) many of their tribes spoke a non-Greek language, and had the habit of eating raw flesh. Apparently the Aetolians set up a kind of united league in early times, but this league first acquired political importance about the middle of the third century BC, and became a formidable rival to the Macedonian monarchs and the Achaean League. The Aetolians took the side of Antiochus III against the Roman Republic, and on the defeat of that monarch in 189 BC, they became virtually the subjects of Rome. Following the conquest of the Achaeans by Lucius Mummius Achaicus in 146 BC, Aetolia became part of the Roman province of Achaea.
The Turks later invaded Aetolia: after a relatively unsuccessful attempt at colonization they took a token amount of slaves and resources from the region, then departed. See Ottoman Greece.
(This article incorporates material from Harry Thurston Peck's Harper's Dictionary of Classical Antiquities (1898) .)