THESSALY, a district of northern Greece, between Mace donia and the Hellenic countries towards the south, and between upland Epirus and the Aegean. It forms an irregular square of about 6o m. in each direction, for the most part level, but with well-marked boundaries, the Cambunian mountains on the north, Othrys on the south, the massive chain of Pindus, the back bone of this part of Greece, on the west ; while at the north-eastern angle is Olympus, separated by the gorge of Tempe (q.v.) from the coast range of Ossa and Pelion, standing in a continuous line to the south-east. Three peaks of Pindus are over 5,000 ft., and Olympus, Ossa and Pelion reach respectively 9,79o, 6,398 and 5,35o feet. The country within these limits is drained by numer ous confluents, which pass into the sea through the gorge of Tempe.
Through Thessaly, therefore, lie all land routes between penin sular Greece arid the north. An important pass from Petra in Pieria debouches west of Olympus on the plain north of Larissa. By this Xerxes entered (Herodotus vii. 173), and when the Greeks heard of this passage, they gave up their defence of Tempe. The main communication with Epirus passed over Mount Lacmon by the upper Peneius to Aeginium in the north-west angle. By this route Julius Caesar arrived before the battle of Pharsalia. Another pass, farther south by Gomphi, leads to the Ambracian gulf. The great southern pass of Coela crosses Mount Othrys nearly north of Thermopylae.
Though Thessaly is the most level district of Greece, it is composed of sections, divided by ranges of hills; Upper Thessaly, to the west and south-west, contains the higher course of the Peneius and all tributaries from the south—Enipeus, Apidanus, Onochonus and Pamisus. Lower Thessaly, from the central ridge west of Larissa to the foot of Ossa and Pelion, is inundated by the Peneius, the flood-water forming the Lake Nessonis, and, when that is full, pouring into Lake Boebe. The chief city of the lower Thessaly was Larissa; in the south at the pass of Coela is another plain, containing a small lake, formerly called Xynias, and low hills separate this from the town of Thaumaki, which overlooks the main upper plain "like a vast sea" (Livy xxxii. 4). The Plain of Pharsalia, intersected by the Enipeus, lies north-east of this, and still farther another battlefield, Cynoscephalae. The political divisions follow the physical, Pelasgiotis being the lower plain of the Peneius, Hestiaeotis and Thessaliotis respectively the north and the south portions of the upper; the fourth, Phthiotis, towards the south-east, was geographically separated by the watershed of Mt. Othrys and its north-east spurs. The landlocked Pagasaeus Sinus (Gulf of Volo), extends from Pagasae at its head to Aphetae at its narrow outlet, where the chain of Pelion turns at right angles to south-west in broken ridges, while on the opposite side rise the heights of Othrys. In the heroic age Phthiotis was the legendary birthplace of Greek navigation in the story of the Argonauts. Hence Achilles came and, according to Thucydides (i. 3), it was the cradle of the Hellenes. Iolcus, the centre of many legends, is near the modern Volo. Near Iolcus, later, Demetrius Poliorcetes founded Demetrias, called by Philip V. of Macedon one of the "fetters of Greece," Chalcis and Corinth being the others.
The history of Thessaly is closely connected with its geography. From the earliest times Thessaly has had a separate history con trolled by its situation. The fertility of the land offered a
temptation to invaders, and was thus the primary cause of early migrations. Its first Neolithic culture combined Danubian char acters with elements from the "Tripolje" culture of Ukraine ; a second phase reinforces the latter elements, at Dimini near Volo. Then long decadence resulted from the spread, first of "Hel ladic," then of "Minyan" culture from the south. Finally, just as Mycenaean exploitation was beginning in the 12th century, fresh northern invaders from Macedonia wrecked all. At this point language and legend supplement archaeology. Thessalian Greek is of the Aeolic group, akin to Boeotian; but between lie the "West Greek" dialects of Phthiotis, Malis, and Doris, subsequently in truded. Aeolic genealogies go back to the early part of the 14th century, whereas the Doric and West Greek expansion is referred to the 12th. Tradition brought both Thessalians and Boeotians from Arne in the north-west, imposing powerful aristocracies on the older inhabitants, who retained political coherence only among the marginal hills in Perrhaebia, Magnesia, and the like. The rich lowlands were the natural home of powerful families such as the Aleuadae of Larissa and the Scopadae of Crannon ; and the ab sence of elevated positions was unfavourable to the foundation of cities, which might have fostered freedom and democracy. The plains, also, were suited to the breeding of horses, and conse quently the force in which the Thessalians were strong was cavalry, a kind of 'troops usually associated with oligarchy. The wealth and the semi-Hellenic character of the people (for, in race, as in geographical position, the Thessalians held an inter mediate place between the Macedonians and the southern Greeks) held them aloof from national sentiment, and at the time of the Persian wars the Aleuadae joined the enemy. United, as under Alexander and Jason, of Pherae, in the 4th century, the Thessa lians were formidable, but they seldom combined for long, and consequently had little influence in Greece. From the 4th to the 2nd century they were usually vassals of Macedon.
For several centuries during the middle ages Rumanian im migrants formed so large a part of the population of Thessaly that that district was called by the Byzantine writers Great Wall achia (Me-yeAn BXaxict); the Jewish traveller, Benjamin of Tudela, so describes it in the latter half of the 12th century. Now, only a few Vlach (Ruman) colonies remain, principally on the west of Olympus and in some gorges of Pindus. The Turkish conquerors settled in the larger towns and in great ranches. The Greeks form so large a majority that, even while the country belonged to the Ottomans, Greek was the official language. Thessaly was ceded to the Greek kingdom by the Porte in 1881. Since that time its prosperity has greatly increased. The port of Volo, almost the only outlet of trade, has a steamer service to Athens. Railways run: (I) from Volo by way of Velestino (ancient Pherae) to Larissa (q.v.); (2) from Velestino to the west by Phersala (Pharsalos), Domokos (Thaumaki), Karditsa and Trikkala (Trika), to Kalabaka (Aeginium), in the upper valley of the Salambria (Peneius) ; (3) the main line from Athens to Salonika enters Thessaly by the Coela pass west of Othrys, reaches Larissa, and proceeds by the gorge of Tempe and the sea front of Olympus. Thessaly is essentially an agricultural and pastoral district.