Columbus, Christopher (1451?–1506), an Italian navigator and explorer. (Christopher Columbus is the Latin form of his name. In Italian it is Cristoforo Colombo; in Spanish, Cristóbal Colón.) His grand dream was to reach Asia by sailing westward across the Atlantic. Although in this he failed, his four voyages to the Americas, 1492–1504, opened the Western Hemisphere to European exploration and colonization. While the Americas had been inhabited for thousands of years, and other Europeans, including the Vikings, may have reached American shores hundreds of years before Columbus, it was his voyages that revealed the existence of this so-called New World to the great powers of Europe.

Columbus's voyages gave rise to an era of European domination of the world and saw the spread of European religious, political, and economic ideas to all parts of the earth. The epoch-making nature of his achievements, however, was recognized by neither Columbus nor his contemporaries.

Columbus was a navigator of extraordinary skill, a religious zealot, and a visionary. He was often daring, courageous, imaginative, and, above all, tenacious. At times, however, he could be inflexible, greedy, jealous, and brutal. A failure as a colonial administrator, he eventually was stripped of all his authority in the Americas and died in obscurity.

Traditionally, Columbus has been revered as the Admiral of the Ocean Sea who discovered America on October 12, 1492, and spread European civilization to the New World. In the late 20th century, however, revisionist historians called Columbus a symbol of European exploitation and imperialism. The controversy created by these contrasting viewpoints has not obscured the central fact that he made what perhaps was the most significant voyage in recorded history and forever changed the world.