To the year 1500 dates the chart by Juan de la Cosa - owner of the caravel "Santa Maria" and fellow of Columbus in the first two voyages - which offers the oldest depiction of the West Indies. In the neck of the parchment there is St. Christopher, with obvious reference to Columbus, whose name means "bearer of Christ." The chart anachronistically follows the style of the portulan charts of the previous century, with the usual grid of rhumbs, multicolored roses and distance scale, but lacks the scale of latitudes, suggesting that the Spanish still practiced dead reckoning.
In 1503 Spain - as Portugal a few years before - was founded the Casa de Contratación, to centralize nautical information and train sea captains, who were subjected to harsh discipline and were not authorized to conduct a ship until they passed public examinations under the supervision of senior captains. But the main function of the Casa de Contratación was to safeguard and update the Padrón Real, established in 1508, similar to the Portuguese Padrão Real, i.e. the portfolio on which new discoveries were recorded. By mid-century the "Casa" had achieved importance, fame and effectiveness such that the polar explorer Stephen Borough suggested to Queen Elizabeth - without success - to create a similar organization in England.
To the prestigious office of Superintendent of the "Casa" came to be called the most famous explorers and cosmographers of the time, such as Juan de la Cosa and Amerigo Vespucci, the latter being made "Pilot mayor" for life in 1508, after gaining Spanish citizenship by reason of its deeds in favor of Spain, second only to Columbus. Among his successors, there was also Sebastian Cabot, from England, who passed to the service of Spain, receiving the appointment as "Piloto mayor" in 1518.
Meanwhile, the Portuguese Ferdinand Magellan, despite having participated in numerous expeditions on behalf of his country, had lost favor with the Court and had retired to private life in 1515, devoting himself to geographical and nautical studies. At that time he developed the belief that the Moluccas were in the hemisphere that the Treaty of Tordesillas assigned to Spain and, therefore, would be reachable from the West. With many difficulties he convinced the Casa de Contratación "Spain to finance an expedition, and departed in 1519 with five ships and 265 men, of which over twenty were Italian, including Antonio Pigafetta, the expedition historian.
Sailing down the coast of South America he reached the Strait that in 1525 took his name, and sailed up the Pacific, which he so named because of its favorable winds and currents. On February 13, 1521 he crossed back the equator, and after a month reached the Marianas and the Philippines, of which he took possession in the name of the King of Spain, and then found his death in a battle with the natives, the following April 27.
The 1500 was the century of "conquistadores" who followed the explorers in search for the riches of the New World, often in opposition to the legal power represented by the governors of the colonies. Among the first famous adventurers there were Vasco Nuñez de Balboa, who reached the Pacific, which he called "South Sea", and Fernando Cortez, conqueror of Mexico between 1519 and 1522. However, since these regions did not seem to offer the expected riches, exploration diverted to South America: Francisco Pizarro and Diego de Almagro seized Peru, Pedro de Valdivia led the conquest of Chile, and countless others pursued the search of the fabled "El Dorado" that caused the rapid reconnaissance of the areas north of the Amazon.
Since the lands south of it fell - by virtue of the Treaty of Tordesillas - under the influence of Portugal, Spain continued penetration in the south of the continent, where they took possession of the Parana and Paraguay, so that by mid-century, all land south of Brazil was in the hands of Spain. Exploration was then resumed in the Pacific, which was by then accessible from inland, the circumnavigation of the continent being no longer necessary. They conquered the Philippines, dedicated to Philip II, and other islands in the eastern Pacific but did not find the sought-for riches, and exploration was virtually abandoned, later passing to the Dutch.
In Spain, meanwhile, the King was opposed in his political absolutism by England, through privateering at sea aimed at weakening the Spanish economy, which culminated in open conflict: in 1588 the 'Invincible Armada was defeated and that event marked the incipient decline of Spanish sea power and the advent of the English supremacy.
When Philip II joined the crowns of Spain and Portugal, he tried to subdue the rebel Protestant provinces of the Netherlands, by closing to them the Portuguese ports from which they importedspices, thus giving rise to their rebellion: Holland created a powerful merchant fleet, which gradually supplanted the Iberian colonial power in the Far East and eventually led, in the seventeenth century, to the Dutch supremacy in the nautical, merchant and charting fields.