Cosa was a Latin colonia founded under Roman influence in southwestern Tuscany in 273 BC, perhaps on land confiscated from the Etruscans (Velleius Paterculus 1.14.7; Livy Periochae 14; Strabo 5.2.8). The Etruscan site (called Cusi or Cosia) may have been where modern Orbetello stands; a fortification wall in polygonal masonry at Orbetello's lagoon may be in phase with the walls of Cosa. The position of Cosa is distinct, rising some 113 metres above sea level and is sited 140 km northwest of Rome on the Tyrrhenian Sea coast, on a hill near the small town of Ansedonia. The town experienced a hard life and was never truly a prosperous Roman city, although it has assumed a position of prominence in Roman archaeology owing to the circumstances of its excavation (cf. Dyson 2005, below). After the foundation, wars of the 3rd century BC affected the town (Livy 22.11.6; 27.10.8-9; 32.2.7; 33.24.8-9). Cosa seems to have prospered until it was sacked in the 60s BC, perhaps by pirates. This led to a re-foundation under Augustus and then life continued until the 3rd century. One of the last textual references to Cosa comes from the work of Rutilius Claudius Namatianus in his De reditu suo. In the passage 1.285-90, Rutilius remarks that by 416 the site of Cosa was deserted and could be seen to be in ruins. He further suggests that a plague of mice had driven the people of Cosa away.
Read more about Cosa: Archaeology, Urban Layout, Capitolium, City Walls and Gates, Forum, Private Houses, Cosa Under The Empire, Middle Ages, Settefinestre, Further Study, Bibliography