Near the end of the 15th century a remarkable new chapter in global history began. Several countries in Western Europe launched maritime expeditions of exploration, systematically sailing thousands of miles across the Atlantic and Pacific Oceans in search of new lands. Sailing the oceans was daring and difficult. And while it may be that other cultures - like the Chinese and the Polynesians - had previously sent out long-distance voyages to explore new areas, there is no evidence that this series of explorations began with the idea of bringing back more and more knowledge about the planet. The Europeans were interested in the size of the continents, their position on the globe, and their relationship to each other. The voyagers were also interested in the people who inhabited lands they did not know, and in the resources of those lands, resources that might be used in European markets. Global maritime exploration and the discovery of new lands and peoples lasted well into the 19th century. Perhaps the most remarkable new lands discovered were North and South America, which the Europeans called the "New World," for their existence had not yet been suspected in Europe. In time the Europeans would discover and map virtually all the land on the globe.

Several factors made possible this "era of discovery." A new confidence in human capability characterized thinking during the Renaissance in Europe and generated curiosity and experimentation. New technologies played a big role in exploration. For example, in the 15th century European ship builders developed the caravel, a light, maneuverable ship with lateen (triangular) sails that navigators could sail into the wind, a remarkable achievement. At the same time astronomers developed the astrolabe, an instrument that allowed sailors to determine their position on the ocean between the equator and the north or south pole. With these and other inventions, European explorers sailed first south around Africa to India and China, and later, west to the New World.

Explorers brought back observations about the continents and the people of distant lands, and information about goods that could be sold for profit by merchants and processed into products that improved the way of life in Europe. Making profit from newly acquired goods and preventing rival countries from gaining control of the supply sources of these goods became driving impulses for exploration. This drive toward making a profit soon drew a number of western European countries into competition. By the beginning of the 18th century, there were only a few regions of the globe they had not probed. One of these was the North Pacific Ocean.

The Europeans encountered people with different cultures in the lands they discovered. Because of their technologies, the Europeans gradually came to dominate the New World. As they did they began to think of themselves as superior to the people in these new lands. This belief in their superiority would still be felt centuries later.