The Florentine navigator Amerigo Vespucci (veh-SPOO-chee) (1454–1512) realized what Columbus had not. Writing about his discoveries on the coast of modern-day Venezuela, Vespucci stated: “Those new regions which we found and explored with the fleet . . . we may rightly call a New World.” This letter, titled Mundus Novus (The New World), was the first document to describe America as a continent separate from Asia. In recognition of Amerigo's bold claim, the continent was named for him.

To settle competing claims to the Atlantic discoveries, Spain and Portugal turned to Pope Alexander VI. The resulting Treaty of Tordesillas (tawr-duh-SEE-yuhs) in 1494 gave Spain everything to the west of an imaginary line drawn down the Atlantic and Portugal everything to the east. This arbitrary division worked in Portugal's favor when in 1500 an expedition led by Pedro Álvares Cabral landed on the coast of Brazil, which Cabral claimed as Portuguese territory.

The search for profits determined the direction of Spanish exploration and expansion in South America. Because its profits from Hispaniola and other Caribbean islands were insignificant compared to Portugal's enormous riches from the Asian spice trade, Spain renewed the search for a western passage to Asia. In 1519 Charles V of Spain commissioned Ferdinand Magellan (1480–1521) to find a direct sea route to the spices of the Moluccas, islands off the southeast coast of Asia. Magellan sailed southwest across the Atlantic to Brazil, and after a long search along the coast he located the treacherous strait off the southern tip of South America that now bears his name (see Map 16.2). After passing through the strait, his fleet sailed north up the west coast of South America and then headed west into the Pacific toward the Malay Archipelago. (Some of these islands were conquered in the 1560s and were named the Philippines for Philip II of Spain.)

Terrible storms, disease, starvation, and violence haunted the expedition. Sailors on two of Magellan's five ships attempted mutiny on the South American coast; one ship was lost, and another ship deserted and returned to Spain before even traversing the strait. Magellan himself was killed in a skirmish in the Malay Archipelago. At this point, the expedition had enough survivors to man only two ships, and one of them was captured by the Portuguese. Finally, in 1522, one ship with only eighteen men returned to Spain, having traveled from the east by way of the Indian Ocean, the Cape of Good Hope, and the Atlantic. The voyage — the first to circumnavigate the globe — had taken close to three years.

Despite the losses, this voyage revolutionized Europeans' understanding of the world by demonstrating the vastness of the Pacific. The earth was clearly much larger than Ptolemy's map had shown. Magellan's expedition also forced Spain's rulers to rethink their plans for overseas commerce and territorial expansion. Although the voyage made a small profit in spices, the westward passage to the Indies was too long and dangerous for commercial purposes. Thus Spain soon abandoned the attempt to oust Portugal from the Eastern spice trade and concentrated on exploiting its New World territories.