Selinus was founded in 651 or 628 BC by colonists from Megara Hyblaea and from Megara in Greece. The city got its name from the wild celery (Greek: selinon) that still grows in the locality. It achieved great prosperity in the 5th century BC, when its great temples were built. By extending its territory, however, Selinus became embroiled in border disputes with the rival city of Segesta (q.v.). After the Carthaginians lost the Battle of Himera in 480 BC, Selinus allied itself with Syracuse against Carthage. The Segestans then appealed to Carthage for help in their struggle against Selinus, and consequently a Carthaginian army of 100,000 men took and destroyed Selinus in 409; the city's walls were razed, and only 2,600 of its inhabitants escaped. Selinus never truly recovered, though it became a Carthaginian tributary and was repopulated. In 250 BC Carthage razed it and transferred its inhabitants to Lilybaeum (modern Marsala).

Excavations have uncovered Selinus' extensive ruins. History notwithstanding, it is surmised that the city's monuments were toppled by earthquakes rather than by the hand of man. The remains of five temples litter the fortified acropolis, while the remains of three more ruined temples bearing massive Doric columns lie on a hill east of Selinus. The modern Italian town of Selinunte lies nearby.