An important city of the Roman province Macedonia, situated on the Via Egnatia, the overland route from Italy to the E., and at the north-eastern corner of the Thermaic Gulf. Its buildings rose above one another in tiers on the slopes of the hills. The situation is in every respect admirable, and must have been early occupied. This city was founded about b.c. 315, and named after a stepsister of Alexander the Great. Its greatness under Macedonian rule was even extended under Roman rule. It became the capital of the Roman province Macedonia, constituted b.c. 146. It was made a 'free city' in b.c. 42 (Ac 17:5 knows this fact), and was ruled by its own magistrates under the rather rare title 'politarchs,' who were 5 or 6 in number. There were many Jews here, as the possession of a synagogue shows (Ac 17:1), and a number of proselytes (Ac 17:4). The enemies of St. Paul raised a cry of treason, and a serious riot resulted. Some of Paul's friends had to give security that this would not be repeated. This forced Paul to leave the city. Members of the church here were Jason, Gaius, Secundus, Aristarchus. See Thessalonians.