The European era of expansion and exploration did not begin with Columbus or the late fifteenth-century Portuguese attempts to find a sea passage to India. Europeans had come into increasing contact with other lands centuries before that. The Norse discovered and settled lands throughout the North Atlantic; Crusaders returning from the Middle East whetted European appetites for the spices, textiles, and other commodities. Trade with those regions increased substantially in the thirteenth and fourteenth centuries since the Mongols welcomed Christian traders to cross their lands in safety. But afterward, Islamic states preferred to keep the profits of long-distance trade to themselves. New sea routes developed in the sixteenth century allowed Jesuit missionaries and Dutch, Portuguese, and British merchants to establish direct contacts with the Far East, Southern Asia, and Russia. Although these Europeans brought back many accounts of the peoples of Asia, they were a mixture of fact and fantasy that would characterize Western views of the East long after the Age of Discovery.

Europeans who wished to travel to Asia were increasingly troubled by the slow and dangerous land route to India and China and they began to look for other routes to Asia, often deciding that a southward sea route might be possible. With the patronage of the Portuguese Prince Henry, ships flying his flag began slowly to navigate down the unfamiliar and treacherous West African coast in search of a passage to India. European explorers, and the merchants and missionaries who followed them, were motivated both by commercial desires and by a religious motivation to discover Prester John, who purportedly ruled now in eastern Africa. Already within the next century, Europeans traders had began to exploit and expand pre-existing African slaving systems to satisfy a demand for labor in the newly conquered Americas. The opening of the trans-Atlantic slave trade in the fifteenth century presaged an enormous transformation of the globe as huge numbers of Africans were forcibly transported to toil on a new continent. This aspect of African slavery has been much studied by historians who have sought to chronicle, explain, understand, and quantify the effects of this trade on the modern world. Consequently, modern scholars have shown ways in which both Africans and Europeans transformed the Atlantic world, creating new systems of government, language, and worship, as well as many of the problems facing African and American societies today.

Beginning with Christopher Columbus's first voyage in 1492, European explorers attempted to sail west from Europe to reach China. In taking this route, Europeans made their first contact with the Americas, which they called "the new world." Between 1492 and 1600, nearly 200,000 Spaniards alone immigrated to the New World. Two of these Spaniards, Hernan Cortes and Francisco Pizarro, led expeditions that conquered the two greatest civilizations in the Americas, the Aztecs and the Incas. Although Spain led the way in the conquest of the Americas, the Portuguese, French, and English soon followed. By the early 1600s, with the establishment of the colony of Jamestown in Virginia, Europeans had explored virtually all of the present-day continents of North and South America, and had established a new system of world trade in the process. The exploration and subjugation of the New World by the old one brought with it numerous economic, political, and cultural changes that are explored in the documents that follow.

During the fifteenth and sixteenth centuries, as Europeans explored the world, they were able to create more and more detailed maps and charts of Africa, Asia, and the Americas. Of course, none of these voyages would have been possible were it not for improvements made to navigational instruments such as the astrolabe. The technological achievements of the period both resulted from and enabled European exploration and expansion. They serve, therefore, as the focus of this module.