The Phlegraean Fields around Naples has been inhabited since the Neolithic period. The earliest Greek settlements were established in the Naples area in the second millennium BC.
Sailors from the Greek island of Rhodes established a small commercial port called Parthenope (Παρθενόπη, meaning “Pure Voice”) on the island of Megaride in the ninth century BC.By the eighth century BC, the settlement had expanded to include Monte Echia.In the sixth century BC, after the decline of Parthenope, the new urban zone of Neápolis (Νεάπολις) was founded on the plain, eventually becoming one of the foremost cities of Magna Graecia.
The city grew rapidly due to the influence of the powerful Greek city-state of Syracuse, and became an ally of the Roman Republic against Carthage. During the Samnite Wars, the city, now a bustling centre of trade, was captured by the Samnites; however, the Romans soon captured the city from them and made it a Roman colony. During the Punic Wars, the strong walls surrounding Neápolis repelled the invading forces of the Carthaginian general Hannibal.