The Greek city of Cumae was founded in 8th century BC in an area towards the southern Etruscan border. By 504 the southern Etruscans were defeated by the Cumaeans, but they still maintained a powerful force. In 474 they were able to raise a fleet to launch a direct attack on Cumae.
After he was called for military assistance Hiero I of Syracuse allied with naval forces from the maritime Greek cities of southern Italy to defend against Etruscan expansion into southern Italy. In 474 they met and defeated the Etruscan fleet at Cumae in the Bay of Naples. After their defeat, the Etruscans lost much of their political influence in Italy. They lost control of the sea and their territories were eventually taken over by the Romans, Samnites, and Gauls. The Syracusans dedicated a captured Etruscan helmet at the great panhellenic sanctuary at Olympia, a piece of armour found in the German excavations there. The Etruscans would later join the failed Athenianexpedition against Syracuse in 415 BC, which contributed even further to their decline.
The battle was later honored in Pindar's first Pythian Ode.