AETOLIA, a district of northern Greece, bounded on the south by the Corinthian Gulf, on the west by the river Achelous, on the north and east by the western spurs of Parnassus and Oeta. The land naturally falls into two divisions. The basins of the lower Achelous (mod. Aspropotamo) and Euenus (Phidharis) form a series of alluvial valleys intersected by detached ridges which mostly run parallel to the coast. This district of "Old Aetolia" lacks a suitable sea-board, but the inland, and especially the plain of central Aetolia lying to the north of Lakes Hyria and Trichonis and Mount Aracynthus,forms a rich agricultural country. The northern and eastern regions are broken by an extensive com plex of chains and peaks, whose rugged limestone flanks are clad at most with stunted shrubs and barely leave room for a few pre carious mule-tracks. These heights often rise in the frontier ranges of Tymphrestus, Oxia and Corax to more than 7,000 ft.; the snow-capped pinnacle of Kiona attains to 8,240 ft. A few defiles pass through this barrier to the other side of the north Greek watershed.
In early legend Old Aetolia, with its cities of Pleuron and Caly don, figures prominently. During the great migrations (see DORIANS) the population was largely displaced, and the old inhabi tants long remained in a backward condition. In the sth century some tribes were still living in open villages under petty kings, addicted to plunder and piracy, and hardly recognized as Hellenes at all. Yet their military strength was not to be despised: in 426 their archers and slingers easily repelled an Athenian invasion under Demosthenes. In the 4th century the Aetolians began to take a greater part in Greek politics, and, in return for helping Epameinondas (367) and Philip of Macedon (338), recovered con trol of their sea-board, to which they annexed the Acarnanian coast and the Oeniadae. Aetolia's prosperity dates from the pe riod of Macedonian supremacy. It may be ascribed partly to the wealth and influence acquired by Aetolian mercenaries in Hellen istic courts, but chiefly to the formation of a national Aetolian league, the first effective institution of this kind in Greece. Created originally to meet the peril of an invasion by the Mace donian regents Antipater and Craterus, who had undertaken a punitive expedition against Aetolia after the Lamian War (322), and by Cassander (314-3i I), the confederacy grew rapidly during the subsequent period of Macedonian weakness. Since 290 it had extended its power over all the uplands of central Greece, where its command over Heracleia (28o) provided it with an important defensive position against northern invaders, its control of Delphi and the Amphictyonic council with a useful political instrument. The valour of the Aetolians was conspicuously displayed in 279, when they broke the strength of the Celtic irruption by slaughter ing great hordes of marauders. The commemorative festival of the Soteria, which the league established at Delphi, obtained recognition from many leading Greek states. After annexing Boeotia (by 245) the Aetolians controlled all central Greece. En deavouring next to expand into Peloponnesus, they allied them selves with Antigonus Gonatas of Macedonia against the Achaean league (q.v.), and besides becoming protectors of Elis and Messenia won several Arcadian cities. Their naval power ex tended to Cephalonia, to the Aegaean islands and even to the Hellespont. The league at its zenith had thus a truly imperial status.
Later in the century its power began to be sapped by Mace donia. To check King Demetrius (239-229) the Aetolians joined arms with the Achaeans. In 224 they held Heracleia Trachis against Antigonus Doson, but lost control of Boeotia and Phocis. Since 228 their Arcadian possessions had been abandoned to Sparta. At the same time a new enemy arose in the Illyrian pirate fleets, which outdid them in unscrupulousness and violence. The raids of two Aetolian chiefs in Achaean territory (220) led to a coalition between Achaea and Philip V. of Macedon, who as sailed the invaders with great energy, driving them out of Pelopon nesus and marching into Aetolia itself, where he surprised and sacked the federal capital Thermon. After buying peace by the cession of Acarnania (217) the league concluded a compact with Rome. In the great war of their Roman allies against Philip the federal troops took a prominent part, their cavalry being largely responsible for the victory of Cynoscephalae (197). The Romans in return restored central Greece to the league, but by withholding its former Thessalian possessions excited its deep resentment. The Aetolians now invited Antiochus III. of Syria to European Greece, and so precipitated a conflict with Rome. But in the war they threw away their chances. In 192 they wasted themselves in an unsuccessful attempt to secure Sparta. In 191 they supported Antiochus badly, and by their slackness in the defence of Thermopylae made his position in Greece untenable. Having thus isolated themselves the Aetolians stood at bay be hind their walls against the Romans, who refused all compromises, and, after the general surrender in 189, restricted the league to Aetolia proper and assumed control over its foreign relations. By the time of Sulla, the functions of the Aetolian league had become purely nominal. The federal constitution closely re sembled that of the Achaean league (q.v.), for which it doubtless served as a model. The general assembly, convoked every autumn at Thermon to elect officials, and at other places in special emergencies, shaped the league's general policy; it was nominally open to all freemen, though no doubt the Aetolian chieftains really controlled it. The council of deputies from the confederate cities undertook the routine of administration and jurisdiction. The strategus (general), aided by 3o apocleti (ministers), had com plete control in the field and presided over the assembly, though with restricted advisory powers. The Aetolians also used the Amphictyonic synod for passing solemn enactments. The league's relation to outlying dependencies is obscure ; many of these were probably mere protectorates or "allied states" and secured no representation. The federal executive was certainly much more efficient than that of the Achaeans, and its councils suffered less from disunion ; but its generals and admirals, official or otherwise, enjoyed undue licence; hence the league deservedly gained an evil name for the numerous acts of lawlessness or violence which its troops committed. But as a champion of republican Greece against foreign enemies no other power of the age rendered equal services. In the 15th century Aetolia passed under the rule of Scanderbeg and the Venetians, but was finally conquered for the Turks by Mohammed II. In the War of Independence it was the scene of severe fighting, including the sieges of Missolonghi.
(M. C.) pp. sqq.; Thucydides iii. 94-98 ; Dio dorus xviii. 24. 5; Pausanias R. 20 sq.; Polybius and Livy passim; W. J. Woodhouse, Aetolia (Oxford, 1897) ; M. Dubois, Les Ligues acheenne et itolienne (Paris, 1885) ; E. A. Freeman, Federal Govern ment ch. vi. (ed. 1893, London) ; B. V. Head, Historia Numorum, PP. 283-284 (Oxford, 1887) ; M. Holleaux in Bulletin de Correspon dance Hellenique, pp. 362-372 (19o5) ; G. Sotiriades in Apxa.,X07,Ki pp. (two), pp. (1903), and in Bulletin de Correspondance Hellinique, pp. 139-184 (1907) ; C. Salvetti in Studi di Storia Antica, vol. ii. pp. 27o-320 (Rome, 1893).