After the collapse of Roman naval power, while the rest of Europe was engulfed in petty wars among petty kingdoms, the Venetians created the longest-lasting republic in Europe.  They developed a reputation as skilled sailors capable of handling ships safely along unforgiving coastlines.  As early as the mid 500s, little marshy Venice had twice sent its fleet to assist mighty Constantinople, and by the 880s, Venice had earned the gratitude of maritime nations at both ends of the Mediterranean by putting down the pirates infesting the Dalmatian coastline. By that time, Venice was already the leading clearing port for goods in the Med, especially precious metals, and her prestige was further enhanced when she fought off an attack by the Magyars who had been devastating Eastern Europe and northern Italy. A Venetian fleet was clearly not something to mess with.

October 7th, 1571, a naval battle between the Christians and Ottomans fought in the strait between the gulfs of Pátrai and Corinth, off Lepanto, Greece.  The fleet of the Holy League commanded by John of Austria (d. 1578) opposed the Ottoman fleet under Uluç Ali Pasha. The allied fleet (about 200 galleys, not counting smaller ships) consisted mainly of Spanish, Venetian, and papal ships and of vessels sent by a number of Italian states. It carried approximately 30,000 fighting men and was about evenly matched with the Ottoman fleet.

The battle ended with the virtual destruction of the Ottoman navy (except 40 galleys, with which Uluç Ali escaped). Approximately 15,000 Turks were slain or captured.  Some 10,000 Christian galley slaves were liberated.

Lepanto was the first major Ottoman defeat by the Christian powers, and it ended the myth of Ottoman naval invincibility. It did not, however, affect Ottoman supremacy on the land, and a new Turkish fleet was speedily built by Sokollu, grand vizier of Selim II. Nevertheless, the battle was decisive in the sense that an Ottoman victory probably would have made the Ottoman Empire supreme in the Mediterranean.