On a November day in 1095, in Auvergne, France, Pope Urban II gave one of the most important speeches in world history as he presided over an assembly of important clergymen and officials of the Catholic Church. In his fiery speech, he described the encroachment of the Muslims in Byzantine and in the holy places of Jerusalem. He urged his listeners to begin a holy war against the forces of Islam, and thus the First Crusade was born.

Transformations in Shipbuilding

That day in France, Pope Urban launched more than a religious war, however. During the two centuries that the eight Crusades would last, a radical transformation in world exploration, cross-cultural exchange and trade occurred. Because European armies unprecedented in size needed to be transported long distances, shipbuilding became a thriving industry. Crusaders returning from the Middle East brought with them perfumes, spices, silk tapestries and gems, as well as food items like rice, spices, sherbet, dates and coffee. This created a demand that European traders -- especially those in Spain, Portugal and Italy, countries with coastlines as long as their sea-faring traditions -- were only too happy to fill.

Trade Turns to Exploration

These riches, however, were scarce, and this led European explorers further afield in search of new trading opportunities -- the voyages of Marco Polo, begun as the last Crusades were drawing to a close, are a classic example of for-profit trading journeys turning into ones of exploration. Some historians claim that Christopher’s Columbus’ voyages to America were an indirect result of the Crusades, since one of Columbus' goals was to thwart "the sect of Mahomet," as he wrote in his journal. Going even further, Carol Delaney, author of “Columbus and the Quest for Jerusalem," argues that Columbus’ first voyage was the direct result of a desire to find gold with which to finance a new Crusade to retake Jerusalem from the Muslims. (However, this point of view is disputed by historians and remains highly controversial.)

A Cross-Cultural Exchange

Another effect of the Crusades was to expose Europe to Islamic science, mathematics, art and military science. Europeans learned about chess, algebra, Arabic numbers and irrigation from the Islamic world. Ironically, the Muslims became better builders of fortified castles after the Crusader invasions, and these innovations found their way back to Europe. Muslim universities, established as early as the 7th century, became models for European universities. And Muslims themselves benefited from the trade in textiles from Byzantium and northern Europe.

Military Failure, Cultural Success

The Crusades were a military failure for Christianity, since Christians did not ultimately succeed in their stated goal of recovering the Holy Land from the Muslims. However, they were in fact a political and cultural victory for Europe on a grand scale. The Crusades opened up new trading markets, new ideas and new global vistas to Europeans. Thomas F. Madden, author of “The New Concise History of the Crusades,” writes, “It is one of the remarkable events in history that the Latin West … suddenly burst forth with amazing new energy, neutralizing its enemies and expanding across the globe.”