city, Abruzzi regione, central Italy, on a hill overlooking the Pescara River, south of Pescara. It originated as Teate, chief town of the Marrucini (an ancient Italic tribe), and was taken by the Romans in 305 BC. Destroyed by the barbarians and rebuilt by Theodoric the Ostrogoth king in the 6th century, it was successively a Lombard stronghold, a Norman county, and a possession of the Hohenstaufens, the Angevin dynasty (house of Anjou), the house of Aragon, and the Caracciolo. Its ancient name was applied to the religious order of the Theatines, founded in 1524 to combat Lutheranism and to reform morality. Roman monuments include the ruins of a theatre and of three small temples and the octagonal Church of Santa Maria del Tricalle, built on the site of the pagan temple of Diana Trivia. The 11th-century cathedral, frequently rebuilt, has a Gothic bell tower (1335–1498). Chieti contains the National Museum of Archaeology, the Institute of Art, a theological university, and a provincial library and picture gallery.

The city is divided into the old town on the hill and a rapidly developing industrial and commercial area (Chieti–Scalo) in the valley, where there are branches of several national industries including textile, cellulose, sugar, wire, and tobacco factories. Pop. (2006 est.) mun., 55,751.