In 1095, Pope Urban II received a desperate plea from Byzantine Emperor Alexius I. Muslim invaders had seized the Holy Land and were now moving on Byzantium. In response, Urban issued a decree calling upon the faithful to take up arms. What followed was two centuries of intermittent warfare known collectively as the Crusades. Although they ultimately failed to drive the Muslims from either Jerusalem or Byzantium, the Crusades had considerable social consequences for Europe and the Holy Land alike. They also prompted the expansion of trade and learning in Europe. In their own way, the Crusades helped lay the groundwork for the coming Renaissance.

Social Upheaval

While the Crusades enhanced the authority of the Church in Europe, they also caused a great deal of social chaos. Nowhere was this more immediate than in the Holy land itself. Between 1095 and 1291, various cities in the Holy Land repeatedly changed hands between Christian and Muslim invaders, usually with considerable violence involved. In 1099, for instance, Crusaders overran Jerusalem and conducted a citywide massacre of men, women and children. The Crusades also generated unrest in Europe. It now became acceptable to persecute and massacre Jews, who were also seen as enemies of the Church.

Cultural Exchanges

Despite the violence of the Crusades, Middle Eastern and European cultures influenced one another. Christian invaders introduced European-styled feudal estates across the Holy Land, overseeing both trade and agricultural production. They also left behind a considerable architectural imprint. In Jerusalem alone, they built numerous churches, a city gate, a public market and even a hospital. But cultural influence ran the other way as well. Crusaders got their first exposure to Arabian goods, including finely-crafted silks, dyed cottons and glass. They took possession of Middle Eastern furniture and other items, some of which traveled back to Europe with them.

Trade and Exploration

A new interest in Arabian goods helped spark a growth in trade between Europe and Asia. The first to benefit were Italian port cities like Pisa and Genoa, since they were entry points into Europe. Gradually, though, the Italian monopoly was broken as trade made its way north. But the goods that came into Europe did more than simply enhance commerce. They also opened a new era in global navigation, as sea merchants sought out shorter trade routes. Commercial interests were directly responsible for the voyages of Marco Polo, Vasco da Gama and Christopher Columbus.

The Spread of Learning

During the early Medieval period, Islamic scholars made significant gains in mathematics, chemistry, medicine and technology. As early as the 8th Century, the Muslim world had developed dynamic centers of learning and scholarship. Now the Holy Land became an intellectual crossroads, where the Crusaders encountered Islamic learning and carried it back to Europe with them. As the Crusades came to a close in the 1290s, a new era of learning was about to open up in Europe. The cultural achievements that grew out of this Renaissance would be built partly upon the scholarship brought back from the Crusades.