In Greek legend it appears as the place where the Heraclidae built a fleet to invade the Peloponnesus. Whatever the historical validity of this legend, it – together with the above-mentioned meaning of its name – indicates a long-standing reputation as a major shipbuilding place.

In historical times it belonged to the Ozolian Locrians; but about 455 BC, in spite of a partial resettlement with Locrians of Opus, it fell to the Athenians, who peopled it with Messenian refugees and made it their chief naval station in western Greece during the Peloponnesian war. Two major battles were fought at this location. In 404 it was restored to the Locrians, who subsequently lost it to the Achaeans, but recovered it through Epaminondas.

Philip II of Macedon gave Nafpaktos to the Aetolians, who held it till 191 BC, when after an obstinate siege it was surrendered to the Romans. It was still flourishing about 170, but in Justinian I’s reign was destroyed by an earthquake. It was again destroyed by earthquakes in 553 and in the 8th century and so on. From the late 9th century, it was capital of the Byzantine thema of Nicopolis.

Battle of Lepanto.
The Venetian fortress.In the late Middle Ages it was part of the Despotate of Epirus and for a short period part of the Despotates of Angelokastron (1358-1374) and of Arta (1374-1401)[2][3] Afterwards it fell into the hands of the Venetians, who fortified it so strongly that in 1477 it successfully resisted a four month long siege by a Turkish army thirty thousand strong; in 1499, however, it was rumoured to have been sold by the Venetians to the Ottoman Sultan Beyazid II. The Ottomans referred to Naupactos as “İnebahtı” during their rule. The mouth of the Gulf of Lepanto was the scene of the great sea battle in which the naval power of the Ottoman Empire was nearly completely destroyed by the united Papal, Spanish, Habsburg and Venetian forces (Battle of Lepanto, October 7, 1571). In 1687 it was recaptured by the Venetians, but was again restored in 1699, by the Treaty of Karlowitz to the Ottomans.

In the Greek War of Independence it became Greek once more (March 1829). After World War II and the Greek Civil War, its buildings were rebuilt following the prewar architectural design.

Today the population is about 18,000 people. Residential homes align with the Gulf of Corinth over a length of about 3 km and a width of about 1 km.
The port divides the beachfront in two parts. The Western part is called Psani, while the Eastern part Gribovo. Both beachfronts provide the backdrop for a nice promenade while a wide range of restaurants and cafes can also be found.
Nafpaktos sits on a shoulder of a mountain range on the north while farmlands dominate the western part. The climate is one of the best in Greece.

The municipality is mainly made up of mountains while much of the fertile land is within the Gulf of Corinth.

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