John II
John II of Portugal, the only surviving son of King Afonso V, played a significant role in the consolidation of royal power and the advancement of Portuguese exploration during the late 15th century. His early life was steeped in Iberian politics, and he became regent while his father was involved in a war over the Castilian throne. John II is notably remembered for his strategic elimination of noble threats to his authority, which enabled him to strengthen the monarchy and foster connections with the rising merchant class.
A major proponent of maritime exploration, John II was influenced by his great-uncle, Prince Henry the Navigator, and took an active interest in navigation science. His reign saw the establishment of fortified trading posts along the African coast, such as the fortress of São Jorge da Mina, aimed at protecting Portuguese trade interests. He commissioned significant voyages, most notably by Bartolomeu Dias, who discovered a sea route around Africa into the Indian Ocean, opening access to new trade opportunities.
In response to Spanish claims to newly discovered lands following Christopher Columbus's voyage, John II successfully negotiated the Treaty of Tordesillas in 1494, which safeguarded Portuguese interests and facilitated their expansion into South America, particularly Brazil. His reign reestablished Portuguese power and laid the groundwork for the country's dominance in global trade during the early 16th century.
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Subject Terms
John II
King of Portugal (r. 1481-1495)
- Born: March 3, 1455
- Birthplace: Lisbon, Portugal
- Died: October 25, 1495
- Place of death: Alvor, Portugal
John II resumed exploration that took Portuguese seamen to the southern tip of Africa, confirming a southern route to the Indian Ocean. He also negotiated the Treaty of Tordesillas, thereby assuring future Portuguese preeminence in Indian trade and in Brazil. He is also recognized for his ruthless consolidation of royal authority by curbing the power of the Portuguese nobility.
Early Life
The only surviving son of King Afonso V, John II was immersed in Iberian politics from an early age. The Portuguese dynasty of Aviz was relatively young (John II was the grandson of its founder, John I), and it had been seeking to establish itself and to expand its territory.
John accompanied his father, King Afonso, a devout Christian, on North African crusades that conquered Arzila in Morocco. For his participation in this conquest, John was granted a knighthood. Afonso also had aspirations to the throne of Castile. In 1475, he went to war with Castile, challenging Isabella’s claim to that throne. His son, acting as regent while his father was at war, sent troops to boost the Portuguese forces. They were, nonetheless, defeated, ending any hope of laying claim to the Spanish throne.
Early experiences with Iberian politics made John suspicious of the ultimate goals of Ferdinand of Aragon and Isabella of Castile. Although relinquishing claim to the crown of Castile through the Treaty of Alcáçovas (1479), Portugal gained formal acknowledgement that it had sole fishing and trading rights along the entire west African coast.
John II admired the work of his great-uncle, Prince Henry the Navigator, who had encouraged seamen to develop the skills and equipment necessary to sail into the Atlantic. His interest in voyages of trade and exploration increased after 1474, when his father granted him control of trade with African Guinea and the responsibility for Portuguese explorations.
Life’s Work
John II is remembered first for having consolidated royal power in Portugal. It was his ability to subdue the nobility that later earned him recognition as the perfect prince, a ruler who embodied those political qualities Niccolò Machiavelli described in Il principe (wr. 1513, pb. 1532; The Prince , 1640). Learning of conspiracies against his authority, he did not hesitate to make examples of recalcitrant aristocrats. He was responsible for putting to death the duke of Bragança and also his brother-in-law, the duke of Viseu. With the nobility safely under royal control, John II turned to a rising merchant class for support in his most significant ventures, voyages of exploration in the Atlantic.
Like his great-uncle Prince Henry, John II became interested in the science of navigation. Shortly after coming to power, he convened a group of experts in mathematics to establish a scientific method for determining latitude by observing the sun. As Portuguese seamen pressed closer to the equator and then into southern equatorial waters, they found it increasingly difficult to rely on the guiding presence of the North Star. Calculation of latitude based on the sun thus allowed sailors to fix their position more accurately. The work of this group of mathematicians resulted in the early sixteenth century publication of the first European manual of navigation and the first nautical almanac.
Taking advantage of Portugal’s right to explore and trade along the African coast, John II granted the right to Portuguese merchants to establish fortified trading posts in the region. In 1482, the fortress of São Jorge da Mina was constructed on the Guinea coast in order to protect Portuguese trade in slaves, gold, pepper, ivory, and palm oil, marking the southernmost point in the known world.
The king also outfitted caravels at crown expense to pursue voyages of discovery. What he hoped most to discover was a route that would make possible sea trade with India. He also hoped to make contact with the mythical Prester John IIII26IIII , a Christian African king who, King John hoped, would facilitate trade with India. As a result of these Crown-sponsored voyages, Diogo Cão’s expedition arrived at the mouth of the Congo River in 1483. Disappointed that Cão had not found a passageway around Africa into the Indian Ocean, John II commissioned the expedition of Bartolomeu Dias in 1487. Portuguese sailors on this voyage journeyed to the southernmost tip of Africa and realized there was indeed a sea route from the Atlantic into the Indian Ocean, providing access to the rich eastern trade.
During King John’s reign, a number of Italian seamen settled in Portugal. Among them was the Genoese Christopher Columbus, who arrived in Portugal in 1476 and married a Portuguese woman. In 1484, he sought funding from the king to outfit a fleet that would seek a route to the Indies by sailing west rather than south. After consulting with some of his key maritime advisers, John II became convinced that Columbus’s calculations underestimated the circumference of the globe; he therefore declined to fund the expedition.
Sailing for Spain in 1492, however, Columbus did indeed make landfall in a region he believed to be the East Indies. The Spanish kings quickly sought a papal bull granting them control over this newly discovered area. Pope Alexander VI , himself a Spaniard, issued the papal bull Inter Caetera (1493), giving to the monarchs of Spain authority over new lands discovered to the west of a meridian drawn 100 leagues west of the Cape Verde Islands. John, fearing this would give the Spaniards eventual authority over land and islands the Portuguese believed had come under their control in the Treaty of Alcáçovas, lobbied hard with the Spanish monarchs to establish another treaty placing the meridian line farther west. He succeeded in getting Ferdinand and Isabella to agree to a line 370 leagues west of the Cape Verde Islands in the Treaty of Tordesillas (1494), which protected Portuguese rights to the more important sea lanes later used in the India trade. The treaty also allowed them to claim the South American territory that became Brazil.
Significance
John II reestablished Portuguese power after his father’s military loss to Spain and his attempt to claim the crown of Castile. By turning his attention to the Atlantic trade and Portuguese rights to that trade, John II funded the research into new navigational techniques and the voyages themselves, which demonstrated that trade with the East was possible by sailing around the southern tip of Africa. His savvy statesmanship and suspicion of Spanish ambitions allowed him to formulate the treaty that made possible Portuguese control of trade with the East during the first half of the sixteenth century.
Bibliography
Anderson, James. The History of Portugal. Westport, Conn.: Greenwood Press, 2000. Succinct description of politics in the age of exploration, with a focus on the rise and fall of dynasties.
Catz, Rebecca. Christopher Columbus and the Portuguese, 1476-1498. Westport, Conn.: Greenwood Press, 1993. Describes the years Columbus lived in Portugal and the Portuguese influence on the admiral who claimed part of the Americas for Spain.
Livermore, H. V. A History of Portugal. 2d ed. Cambridge, England: Cambridge University Press, 1976. Classic discussion of Portuguese political history and an excellent overview of court intrigue in the fifteenth and sixteenth centuries.
Oliveira Marques, A. H. de. History of Portugal. New York: Columbia University Press, 1972. Sets the politics of the period into a cultural and demographic context, with an emphasis on broad changes in scientific ideas and in the population of Portugal.
Parry, J. H. The Age of Reconnaissance: Discovery, Exploration, and Settlement, 1450 to 1650. Berkeley: University of California Press, 1981. Describes John’s instrumental role in the Portuguese voyages of exploration and the competition with Spain that resulted from Columbus’s plan to reach the East by sailing west.
Russell, P. E. Portugal, Spain, and the African Atlantic, 1343-1490: Chivalry and Crusade from John of Gaunt to Henry the Navigator and Beyond. Brookfield, Vt.: Ashgate, 1995. Includes analysis of a contemporary account describing the visit made to Portugal by an African king during the reign of John II.
Russell-Wood, A. J. R. Portuguese Empire, 1415-1808: A World on the Move. Baltimore: Johns Hopkins University Press, 1998. A history of the expansion of the Portuguese empire, with particular attention to the individuals involved in the voyages that culminated in a Portuguese presence in the four corners of the world.