Causes and Technology of European Overseas Expansion

By the middle of the fifteenth century, a combination of forces pushed European kingdoms out onto the open ocean. The Ottoman capture of Constantinople in 1453 partially closed the overland routes of the Silk Road, sharpening the search for a sea route to Asia, while the desire to obtain spices such as pepper, clove, cinnamon, and nutmeg directly, without Muslim and Venetian intermediaries, gave Portugal and Castile a powerful commercial incentive. Europe's demographic and economic recovery after the Black Death generated surplus capital and population willing to gamble on overseas ventures, a material drive reinforced by a religious one: the impulse to extend the Reconquista and the crusade against Islam into Africa and Asia, including the search for the legendary Christian ruler known as Prester John. Rivalry between the Portuguese crown, under the Avis dynasty, and Castile-Aragon, under the Catholic Monarchs, over control of the Atlantic acted as a further competitive engine, while merchant and banking families from cities such as Genoa, Florence, and Seville supplied much of the financing that made such expeditions possible.