Isauria (īsôr´ēə), ancient district of S Asia Minor, on the borders of Pisidia and Cilicia, N of the Taurus range, in present S central Turkey. It was a wild region inhabited by marauding bands. When the capital, Isaura or Isaura Vetus [old Isaura], a strongly fortified city at the foot of Mt. Taurus, was besieged by the Macedonian regent Perdiccas in the 4th cent. BC, the Isaurians destroyed the town by fire rather than submit to capture. The Isaurians were brought partially under control (76–75 BC) by the Romans, and again by the Byzantines under Justinian I, but were not completely subdued until the arrival in the 11th cent. AD of the Seljuk Turks. The site contains ruins of the town and its fortifications.