an ancient province in the N.W. of Asia Minor, was bounded on the S. by Lydia, on the E. by Phrygia and Bithynia, on the N. by the Propontis and the Hellespont, and on the W. by the Ægean Sea. The name Mysia, however, was often applied to particular parts of this district. The province was divided into five parts,—Mysia Minor, Mysia Major, Troas, Æolis, and Teuthrania. To the first of these the Mysians were originally confined. They had come thither from the country of the Lydians, as Herodotus asserts, or from Thrace, as Strabo maintains, and as their alleged identity with the Mosians implies. Gradually they spread themselves southward, encroaching upon the Trojans, Æolians, and Phrygian settlers, until they had attained sufficient importance to communicate their name to the entire province. Little is known about their history. They are mentioned by Homer among the allies of Priam. This country was subject at one time to the Lydian monarchy. It then formed in succession a part of the third satrapy under the Persians, and a part of the Syrian empire that was formed after the death of Alexander the Great. On the defeat of Antiochus, the last King of Syria, in 65 B.C., it was given by the Romans to Eumenes, King of Pergamus. It was afterwards incorporated in the Roman province of Asia.

Mysia was rendered rugged by Mount Temnus, Mount Ida, Olympus, and other offshoots of Mount Taurus. There were many rivers, of which the principal were Caicus (Ak-sou) in the S., and Æsepus in the N. Pergamum (Bergama), Cyzicus, Abydos, and Adramyttium (Adramytti), were the chief towns.