In total, Columbus made four trips, claiming land in the West Indies for Spain, yet never realizing that he had discovered a land new to the Europeans. In fact, it took time for the Spaniards to realize that the islands discovered by Columbus were part of a large landmass blocking sea passage to Asia. In 1513, Vasco Nunez de Balboa crossed the Isthmus of Panama only to realize that no one had any idea how large the Pacific Ocean was or how far from the Americas Asia might be. Six years later, a Spanish sailor, Ferdinand Magellan became the first man to sail around the globe, confirming that the trip from the Americas to Asia was long indeed, and nearly unsailable due to adverse conditions around the tip of South America. At this time, Spain was exceedingly disappointed in its New World discoveries.
However, around the time that Magellan was sailing around the world, Spanish explorer Hernan Cortes landed in Mexico and proceeded to conquer the native people, the Aztecs. The Aztecs were a society rich in gold and jewels, and with their defeat at the hands of the Spanish, they became a ready-made labor force working to increase Spain's wealth. Several years later, in 1531, Fransisco Pizarro made a similar conquest of the Inca people of Peru, claiming all their riches for Spain as well. Also around this time, the Spanish made land claims in what is now the American Southwest and Southeast.
Toward the later half of the 1500's, England began to rise as a powerful nation. Following in the footsteps of Ferdinand Magellan, Sir Francis Drake circumnavigated the globe, pirating Spanish ships and plundering Spanish forts, yet making no actual claims on land for the English. In 1578, Queen Elizabeth I began her quest for land in America by commissioning Walter Raleigh and Humphrey Gilbert to establish English colonies on any land not already occupied by a European nation. With Spain already occupying most of the south, England's colonization efforts became concentrated in the Northeast and Midatlantic sections of North America.