THESSALY, a division formerly of Greece, and now of the Ottoman empire, lying between N. Lat. 39. and 40. 30., E. Long. 21. 30. and 23. 25.; bounded on the N. by Macedonia, E. by the Gulf of Salonica and Volo (anc. those of Therma and Pagase), S. by the modern kingdom of Greece, the ancient states of Ætolia, Doris, Phocis, and Locris; and W. by Albania, the ancient Epirus. Length from N. to S. 98 miles, extreme breadth 70; area, 5500 square miles. It consists of a rich and well cultivated plain, enclosed on all sides by mountain-ranges; that of Pindus bounding it on the west, the Cambunian Mountains, which terminate in the lofty summit of Olympus, on the north, the parallel ranges of Othrys and Cæta on the south, and those of Pelion and Ossa on the east, a short distance from the sea. The only break in these mountain barriers is the Vale of Tempe in the north-east, through which the Peneus flows into the sea; this river, with its affluents, watering nearly the whole country. The principal productions are corn, rice, wine, silk, olives, tobacco and wool. Thessaly is said to have been originally inhabited by the Bœotians; who, 60 years after the Trojan war, were expelled by a body of Thessalians from Epirus. This account is probably true in substance; for in later times we find in Thessaly, besides the Thessalians proper, a number of other tribes, such as the Perrhæbi on the slopes of Olympus, the Magnesites on those of Ossa and Pelion, the Achæans between Pindus and the Gulf of Pagase, and the Malians between Othrys and Cæta; and there were also a class of serfs, called Penestæ, similar to the Helots at Sparta. The country was anciently divided into four districts called Thessaliotis, Pelasgiotis, Histæotis, and Phthiotis; which were all united under a magistrate called a Tagus; but his authority does not seem to have been very great, and the country was rarely united in counsel or action. Hence there is little in its history that is worth recording; and we most frequently hear of Thessaly only in connection with the dissensions and civil wars of the different cities. Along with the rest of Greece, Thessaly fell under the power of Macedon; and after the Roman conquest, it was made a part of that province. The battle of Pharsalia, between Cæsar and Pompey was fought in this country. The principal modern towns are Larissa, Trikala, Volo, and Ambelakia. Pop. estimated at 500,000.