Ethnology.—Little can be learned from written sources of the origin and character of the Illyrians. The Greek legend that Cadmus and Harmonia settled in Illyria and became the parents of Illyrius, the eponymous ancestor of the whole Illyrian people, has been interpreted as an indication that the Greeks recognized some affinity between themselves and the Illyrians; but this inference is based on insufficient data. Herodotus and other Greek historians represent the Illyrians as a barbarous people, who resembled the ruder tribes of Thrace. Both are described as tattooing their persons and offering human sacrifices to their gods. The women of Illyria seem to have occupied a high position socially and even to have exercised political power. Queens are mentioned among their rulers. Fuller and more trustworthy information can be obtained from archaeological evidence. In Bosnia the lake-dwellings at Butmir, the cemeteries of Jezerine and Glasinac and other sites have yielded numerous stone and horn implements, iron and bronze ornaments, weapons, &c., and objects of more recent date fashioned in silver, tin, amber and even glass. These illustrate various stages in the development of primitive Illyrian civilization, from the neolithic age onward. The Hallstatt and La Tène cultures are especially well represented. (See W. Ridgeway, The Early Age of Greece, 1901; R. Munro, Bosnia-Herzegovina and Dalmatia, Edinburgh, 1900; and W. Radimský, Die neolithische Station von Butmir, Vienna, 1895–1898.) Similar discoveries have been made in Dalmatia, as among the tumuli on the Sabbioncello promontory, and in Croatia-Slavonia. H. Kiepert (“Über den Volkstamm der Leleges,” in Monatsber. Berl. Akad., 1861, p. 114) sought to prove that the Illyrians were akin to the Leleges; his theory was supported by E. Schrader, but is not generally accepted. In Dalmatia there appears to have been a large Celtic element, and Celtic place-names are common. The ancient Illyrian languages fall into two groups, the northern, closely connected with Venetic, and the southern, perhaps allied to Messapian and now probably represented by Albanian.
See K. Brugmann, Kurze vergleichende Grammatik der Indogermanischen Sprachen (Strassburg, 1904); and his larger Grundriss der vergleichenden Grammatik (2nd ed., Strassburg, 1897), with the authorities there quoted, especially P. Kretschmer, Einleitung in die Geschichte der Griechischen Sprachen (Göttingen, 1896): see also Albania.
History.—Greek colonization on the Illyrian seaboard probably began late in the 7th century b.c. or early in the 6th century. The most important settlements appear to have been at Epidamnus (Durazzo), Tragurium (Traù), Rhizon (near Cattaro), Salona (near Spalato), Epidaurum (Ragusavecchia), Zara and on the islands of Curzola, Lesina and Lissa. There is a collection of Greek coins from Illyria in the museum at Agram, and the researches of Professor F. Bulié and others at Salona (see Spalato) have brought to light Greek inscriptions, Greek pottery, &c. dating from 600 b.c. But Greek influence seems never to have penetrated far into the interior, and even on the coast it was rapidly superseded by Latin civilization after the 3rd century b.c. Until then the Illyrian tribes appear to have lived in a state of intermittent warfare with their neighbours and one another. They are said by Herodotus (ix. 43) to have attacked the temple of Delphi. Brasidas with his small army of Spartans was assaulted by them on his march (424 b.c.) across Thessaly and Macedonia to attack the Athenian colonies in Thrace. The earlier history of the Macedonian kings is one constant struggle against the Illyrian tribes. The migrations of the Celts at the beginning of the 4th century disturbed the country between the Danube and the Adriatic. The Scordisci and other Celtic tribes settled there, and forced the Illyrians towards the south. The necessities of defence seem to have united the Illyrians under a chief Bardylis (about 383 b.c.) and his son Clitus. Bardylis nearly succeeded in destroying the rising kingdom of Macedonia; King Amyntas II was defeated, and a few years later Perdiccas was defeated and slain (359). But the great Philip crushed the Illyrians completely, and annexed part of their country. During the next century we hear of them as pirates. Issuing from the secluded harbours of the coast, they ravaged the shores of Italy and Greece, and preyed on the commerce of the Adriatic. The Greeks applied to Rome for help. Teuta, the Illyrian queen, rejected the Roman demands for redress, and murdered the ambassadors; but the two Illyrian Wars (229 and 219 b.c.) ended in the submission of the Illyrians, a considerable part of their territory being annexed by the conquerors. Illyria, however, remained a powerful kingdom with its capital at Scodra (Scutari in Albania), until 180 b.c., when the Dalmatians declared themselves independent of Gentius or Genthius, the king of Illyria, and founded a republic with its capital at Delminium (see Dalmatia: History, on the site of Delminium). In 168 Gentius came into conflict with the Romans, who conquered and annexed his country. Dalmatia was invaded by a Roman army under Gaius Marcius Figulus in 156, but Figulus was driven back to the Roman frontier, and in Dalmatia the Illyrians were not finally subdued until 165 years afterwards. Publius Scipio Nasica, who succeeded Figulus, captured Delminium, and in 119 L. Caecilius Metellus overran the country and received a triumph and the surname Dalmaticus. But in 51 a Dalmatian raid on Liburnia led to a renewal of hostilities; the Roman armies were often worsted, and although in 39 Asinius Pollio gained some successes (see Horace, Odes ii. 1. 15) these appear to have been exaggerated, and it was not until Octavian took the field in person that the Dalmatians submitted in 33. (For an account of the war see Appian, Illyrica, 24-28; Dio Cassius xlix. 38; Livy, Epit. 131, 132). They again revolted in 16 and 11, and in a.d. 6–9 joined the rebel Pannonians. Suetonius (Tiberius, 16) declares that they were the most formidable enemies with whom the Romans had had to contend since the Punic Wars. In a.d. 9, however, Tiberius entirely subjugated them, for which he was awarded a triumph in 12 (Dio Cass. lv. 23-29, lvi. 11-17; Vell. Pat. ii. 110–115). Thenceforward Dalmatia, Iapydia and Liburnia were united as the province of Illyricum.
Latin civilization spread rapidly, the cultivation of the vine was introduced, gold-mining was carried on in Bosnia, and flourishing commercial cities arose along the coast. Illyria became one of the best recruiting grounds for the Roman legions; and in troubled times many Illyrian soldiers fought their way up from the ranks to the imperial purple. Claudius, Aurelian, Probus, Diocletian and Maximian were all sons of Illyrian peasants. It is probable, however, that most of the highland tribes now represented by the Albanians remained almost unaffected by Roman influence. The importance of Illyricum caused its name to be extended to many neighbouring districts; in the 2nd century a.d. the Illyricus Limes included Noricum, Pannonia, Moesia, Dacia and Thrace. In the reorganization of the empire by Diocletian (285) the diocese of Illyricum was created; it comprised Pannonia, Noricum and Dalmatia, while Dacia and Macedonia, together called Eastern Illyricum, were added later. Either Diocletian or after him Constantine made Illyricum one of the four prefectures, each governed by a praefectus praetorio, into which the empire was divided. This prefecture included Pannonia, Noricum, Crete and the entire Balkan peninsula except Thrace, which was attached by Constantine to the prefecture of the East. From the partition of the empire in 285 until 379 Illyricum was included in the Western Empire, but thenceforward Eastern Illyricum was annexed to the Eastern Empire; its frontier was almost identical with the line of demarcation between Latin-speaking and Greek-speaking peoples, and roughly corresponded to the boundary which now severs Latin from Greek Christianity in the Balkan peninsula. The whole peninsula except Thrace was still known as Illyricum, but was subdivided into Illyris Barbara or Romana and Illyris Graeca (Eastern Illyricum with Greece and Crete). The Via Egnatia, the great line of road which connected Rome with Constantinople and the East, led across Illyricum from Dyrrachium to Thessalonica.
In the 5th century began a series of invasions which profoundly modified the ethnical character and the civilization of the Illyrians. In 441 and 447 their country was ravaged by the Huns. In 481 Dalmatia was added to the Ostrogothic kingdom, which already included the more northerly parts of Illyricum,