The fall of Constantinople to the Muslim Ottoman empire in 1453 is the primary social, political, and economic catalyst that led to the Western European exploration and colonization of the New World.
The Ottomans were much less friendly to the Western Europeans than the Byzantine Empire, a last remnant of the Roman empire, had been. The Byzantines had allowed the Europeans to use their overland routes to India and China without charging prohibitively high tariffs or tolls. In addition, the Mediterranean Sea under the Byzantines was relatively safe for travel.
All of that changed under the Ottomans. They charged prohibitively high tolls for overland passage to the Orient, and Barbary pirates added significantly to the risk of sea passage to the East. Europeans suddenly found the profit sucked out of trade with the Orient. However, Europeans were still very much addicted to products from Asia they couldn't produce themselves, such as the spices and silks to which they had become accustomed.
Adversity can lead to change and innovation. Determined to find profitable routes to the Orient, European monarchs financed explorers. When Portugal discovered a route to India around the tip of Africa, the race was on for exploring to find other routes to Asia. This led to the Europeans sailing west and bumping into an unexpected boon—the North and South American continents.
Once the Europeans realized what they had discovered, they grasped the potential and financed both more exploration and permanent colonies that would insure a steady flow of raw materials into Europe. This was a disaster for the native populations in America but an enormous source of wealth and power for Europe.
Power becomes the primary factor that led to the exploration and colonization of the New World. This power exerted itself in social, economic, and political shifts of thought. Nations in Europe began to recognize that the presence of colonies in the New World enabled it to possess more power, enabling them to grow and challenge other nations for power. The desire to accumulate helped to form the primary change in thought that allowed for exploration and colonization of the New World.
The emergence of the European nation state became one of the primary reasons why exploration and colonization of the New World took place. Nations began to grow as a source of power. For example, Spain began to recognize that its own power could grow on the continent with the emergence of colonies. Being able to explore new territories and gain riches from these lands could translate into substantiation of their own nation. The growth of the Spanish armada, or navy, enabled Spain to control the seas around Europe. However, it was becoming evident as England developed its own formidable naval fleet that a new horizon of power was needed. Politically, nations like Spain, England, and France understood that in order to bolster their own strength on the continent, there would have to be an influx of capital and resources apart from it. European nations had emerged on the continent and recognized that the only way to effectively challenge one another was to generate wealth and accumulate materials from abroad. European absolutism became the political approach of the day. Nations were not necessarily interested in coexisting, as much as establishing and growing their own power base which could be parlayed into challenging other nations' base of power. It was this mode of thought that triggered the exploration and colonization of the New World. Nations were able to explore and colonize the New World and generate money, profit, and strength for their own nation.This becomes one of the dominant themes that explains both the exploration and colonization of the New World and the exploitation and domination of indigenous people that represents one of its legacies.
From an economic point of view, mercantilism becomes the accepted philosophical approach that justified the exploration and colonization of the New World. Mercantilism was an economic point of view that placed colonies at the center of a nation's importance. Mercantilism asserted that the more precious metals and resources a nation owned, the wider a nation's wealth and power base could be expanded. Economically, nations that embraced mercantilism felt the need to increase colonization through exploration of the New World. With its emphasis on government control of the economy, mercantilism became the economic form of national absolutism. The political emergence of the nation- state was intellectually fortified by a mercantilist system that placed the nation- state as the primary broker of economic affairs. The consolidation of power that was sought in mercantilism made it necessary to explore and colonize the New World. The natural and human resources found in the New World became immediately appropriated by European governments in their attempts to increase power. Given the emphasis on Mercantilist philosophy, nations in Europe recognized that if they did not find and control colonies in the New World, their competitors would. The need to economically consolidate control over a nation's affairs helped to justify and expand colonization of the New World.
From a social standpoint, colonization and exploration were seen as means to increase European spirituality. For example, Spanish colonization involved the proselytization of indigenous people. A significant portion of Spanish exploration was rooted in this idea. In May 1493, Pope Alexander VI requested that conversion accompany colonization. As a result, when Columbus returns to the New World, Benedictine Friars accompany him. In England, a part of the Separatist movement was the Pilgrims and their desire to find a religious haven helped them facilitate their entry into the New World. The social force of religion helped play a significant role in the colonization and exploration of the New World. The social timbre of nations in Europe was more "other- directed," no longer being content with life within their own sphere of influence. The desire to seek new horizons and conquer them became a part of the European social understanding, one that helped to facilitate colonization of the New World.