On October 7, 1571, the fleet of the Holy League, consisting of 202 galleys and 6 galleys, entered the Gulf of Lepanto to face the largest fleet the Mediterranean had seen up to that point: 250 Ottoman galleys with more than 30,000 soldiers, and 50,000 sailors and oarsmen.
It all started a few months earlier, when the Christian coalition was encouraged by Pope Pius V to save the Venetian colony of Famagusta on the island of Cyprus, which had been besieged by the Ottomans in the spring of 1571. A year earlier, the other possessions of Venice in Cyprus, including Nicosia.
Having received a blessing from the Pope, the fleet reached the Kingdom of Naples on August 14, 1571. There in the Basilica of St. Clare, after long discussions, Don Juan of Austria was appointed as the leader of the coalition.
Despite the bad weather, the Christian ships sailed south and on October 6, 1571 they reached the port of Sami on the island of Kefalonia.
The odds were against the Christian fleet, but its captain, 24-year-old Don Juan, decided to attack the Ottomans immediately. Although young, he was no stranger to sea battles. Six years earlier he had joined a naval armada sent to rescue Malta and participated in Don García's landing force where a mere 8,000 Spanish troops secured a beachhead and then attacked an outnumbered Ottoman besieging force. Now the young noble would win the greatest battle of his life. Unlike his Ottoman kinsman, who made rich promises to his enslaved Christian oarsmen, Don Juan of Austria was laconic. “There is no heaven for cowards!” That's what Don Juan said. In the middle of the day, when the battle was going badly for the Christian fleet, the Venetians and the Spanish held their ground.
When the day was over, the Ottoman fleet was destroyed, with over 50 ships sunk and 140 captured. Over 20,000 Ottoman soldiers were killed, the elite Janissary Corps lost almost all of its soldiers, and the Ottoman Empire lost most of its experienced sailors – a loss she could not recover for several generations. 12,000 Christian slaves were freed, a rich reward for the 7,500 casualties suffered by the Christian coalition during the battle.
There were three technological advances that won the battle.
The first was metallurgy. While the smelting of iron and bronze has always been done for the production of armor and hand weapons and tools, the refinement of the cannon in the 13th and 14th centuries required a much better development of technology.
The effectiveness of the cannon against fortified cities and large armies forced European governments and entrepreneurs to develop the metallurgical process so that more cannons could be produced at a lower cost. Byzantium also produced enough artillery to defend its capital in 1396 against an Ottoman siege. At the time, the Muslim world had nothing to compare with the advances in European metallurgy, and the Ottomans had no guns. They were forced to retreat, but they learned their lesson.
About 50 years later, the Ottoman Empire still had no developed metallurgy, but was able to buy 68 cannons from Hungary and thus captured Constantinople in 1453, defeating a meager force of 7,000 defenders.
In 1571, Europe, tiny as it was in terms of population compared to the Ottoman Empire, could produce cannons much faster and cheaper than anyone else in the world.
On that morning of October 7, the small number of Christian galleys were loaded with guns: somewhere between 1,500 and 1,800 guns of various sizes compared to only 700 of the great Ottoman fleet. Not to mention that the Ottomans did not have enough ammunition. Most of the Muslim ships sank before they got far enough for their weapons to be effective.
The second factor was firearms. Metallurgical progress not only allowed Christians to have more and better guns, it also put better personal firearms in the hands of Christian soldiers. By 1571 the manufacture of firearms had become a flourishing business, and certain uniformity in caliber and ammunition had been achieved. The manufacture of cast iron was more perfected in Europe than anywhere else. In addition to the production of cast iron cannonballs, which helped artillery, the production of cast iron musket and arquebus barrels also helped. European armories set about producing the greatest amount of firearms the world had ever seen. (Muskets became so cheap that every family could afford one, and indeed, only 40 years after Lepanto the poorest of the Puritan settlers in Massachusetts could own one or more muskets.)
The Ottomans were still aided by the complex bows. The last time Europe had seen such a large-scale battle of archers was two centuries earlier, in the Hundred Years' War.
The third technological factor was the galeas.
Ever since the advent of cannons, the problem of shipyards has been “How to assemble large cannons on the deck of a ship without interfering with the oarsmen?” The Venetians responded by inventing the galeas.
The first six galleys built were used at Lepanto. In fact, two were intended for Giovanni Andrea Doria's south wing and did not go into action until later in the day. The other four won the battle.
The Turks knew nothing of the new type of vessel, so they assumed that the galeas were some kind of reserve ships that would be easily defeated and captured. The four galleys were sent far ahead, about half a mile in front of the Christian line. Most of the Turkish right flank and center focused on capturing the Galeas. When the enemy was within range, the huge monsters opened their battlements and fired.
A post-battle estimate indicates that over 70 Ottoman galleys (one-third of Ottoman losses) were either sunk or disabled by the four galleys.
The Battle of Lepanto marked the beginning of Christendom's technological superiority. The heroism of Christian soldiers and sailors was aided by the intellectual curiosity and entrepreneurial courage of European scientists, artisans and entrepreneurs. A little forgotten fact is that Miguel de Cervantes participated in the battle and lost his left arm in it.