John III (or João III, 7 June 1502 – 11 June 1557), nicknamed o Piedoso ("the Pious"), was the fifteenth King of Portugal and the Algarves.

Born in Lisbon, he was the son of King Manuel I and his queen consort, Maria of Aragon (the third daughter of King Ferdinand II of Aragon and Queen Isabella I of Castile). John succeeded his father in 1521, at the age of nineteen. During his rule, Portuguese possessions were extended in Asia and in the New World through the Portuguese colonization of Brazil. John III's policy of reinforcing Portugal's bases in India (such as Goa) secured Portugal's monopoly over the spice trade of cloves from the Moluccas and nutmeg from the Banda Islands, as a result of which John III has been called the "Grocer King". On the eve of his death in 1557, the Portuguese empire spanned almost 1 billion acres. During his reign, the Portuguese became the first Europeans to make contact with both China, under the Ming Dynasty, and Japan, during the Muromachi period. He abandoned Muslim territories in North Africa in favor of trade with India and investment in Brazil. In Europe, he improved relations with the Baltic region and the Rhineland, hoping that this would bolster Portuguese trade. John was responsible for the evangelization of the Far East and Brazil, in part through the introduction of Jesuit missions there. Both the Jesuits and the Portuguese Inquisition, introduced in 1536, were to become key institutions in Portugal and its Empire. The Jesuits were particularly important for mediating Portuguese relations with native peoples and the Inquisition served to spare Portugal the civil upheavals of religious warfare of the sort that occurred in France and elsewhere in Europe during the 16th century. In the final years of John's reign, Portugal's colony of Brazil was just beginning its rapid development as a producer of sugar that compensated for the gradual decline of revenues from Asia, a development that would continue during the reign of his grandson and successor, Sebastian, who became king upon the death of John of apoplexy in 1557.

Prince John, the eldest son of King Manuel, was born on 6 June 1502. The event was marked by a masterpiece of Portuguese theater, Gil Vicente's Visitation Play, or: the Monologue of the Cowherd (Auto da Visitação ou Monólogo do Vaqueiro) presented in the Queen's chamber. The young prince was sworn heir to the throne in 1503, the year his youngest sister, Isabella of Portugal, Consort Empress of the Holy Roman Empire between 1527 and 1538 was born. King John III, was educated by notables of the time, including the astrologer Tomás de Torres and Diogo de Ortiz, Bishop of Viseu. One of his teachers was Luís Teixeira, a humanist educated in Italy. John's chronicler said that "Dom João III faced problems easily, complementing his lack of culture with a practice formation that he always showed during his reign" (António de Castilho, Elogio d'el-rei D. João de Portugal, terceiro, do nome). In 1514, he was given his own house, and a few years later began to help his father in administrative duties.

At sixteen he was chosen to marry his first cousin, the 20 year old Eleanor of Habsburg, eldest daughter of Philip the Handsome of Austria - Burgundy and queen Joanna of Castile, but instead she married his widowed father King Manuel I. John took deep offence at this: his chroniclers say he became melancholic and was never quite the same. Some historians also claim this was one of the main reasons that John later became fervently religious.

On 19 December 1521, at the age of 19, he was crowned king in the Church of Saint Dominique in Lisbon, beginning a thirty-six year reign characterized by intense activity in internal and overseas politics, especially in relations with other major European states.

The marriage of John's sister, Infanta Isabella of Portugal, to Charles V enabled the Portuguese king to forge a stronger alliance with Spain and the Holy Roman Empire. To strengthen his ties with Austria, he married his maternal first cousin Catherine of Habsburg, younger sister of Charles V and his erstwhile fiancée Eleanor, in the town of Crato. John had nine children from that marriage, but most of them died young. By the time of John's death, only his grandson, Sebastian, was alive to inherit the crown.

John III continued to centralize the absolutist politics of his ancestors. He called for the Cortes only three times and at great intervals: 1525 in Torres Novas, 1535 in Évora and 1544 in Almeirim. He also tried to restructure administrative and judicial life in his realm.
Toward the end of John III's reign, Portugal entered a period of serious economic, social, and political problems, resulting in the wane of Portuguese power.

The large and far-flung Portuguese Empire was difficult and expensive to administer, and was burdened with huge external debt and trade deficits. Portugal's Indian and Far Eastern interests grew increasingly chaotic under the poor administration of ambitious governors. John III responded with new appointments which proved troubled and short lived: in some cases, the new governors even had to fight their predecessors to take up their appointment. The resulting failures in administration brought on a gradual decline of the Portuguese trade monopoly.

Among John III's many governors of this region, were Vasco da Gama, Henrique de Meneses, Pedro Mascarenhas, Lopo Vaz de Sampaio, Nuno da Cunha, Estêvão da Gama, Martim Afonso de Sousa and João de Castro.

Overseas, the Empire was threatened by Turkey in both the Indian Ocean and North Africa, causing Portugal to increase spending on defense and fortifications. Meanwhile, in the Atlantic, where Portuguese ships already had to withstand constant attacks of corsairs, an initial settlement of French colonists in Brazil created yet another "front". The French made alliances with native South Americans against the Portuguese and military and political interventions were used. Eventually they were forced out, but not until 1565.

In the first years of John III's reign, explorations in the Far East continued and the Portuguese reached China and Japan; however, these accomplishments were offset by pressure from a strengthening Ottoman Empire under Suleiman the Magnificent, especially in India where attacks became more frequent. The expense of defending Indian interests was huge. To pay for it, John III abandoned a number of strongholds in North Africa (Safim, Azamor, Alcacer Ceguer and Arzila).

All of John III's children died before him, although one son, also named John, had sired a child by Joan of Spain before he died. This posthumous son became King Sebastian I (1557 – 1578). Sebastian had no children. After his early death the crown passed to his great-uncle Cardinal Henry I (John's brother). He, too, had no children and reigned for only two years (1578 – 1580). The ensuing dynastic crisis opened the way for Philip II of Spain (Philip I of Portugal) to take over Portugal for the Habsburg dynasty.

The reign of John III was marked by diplomacy. With Spain, he made alliances through marriage (himself with Catherine of Spain; Isabella, princess of Portugal with Charles V; Maria, princess of Portugal – his daughter – with Philip II of Spain, and others) which ensured peace in the Iberian Peninsula for a number of years. However, the intermarriage of these closely related royal families may have been one of the factors contributing to the poor health of John's children and of future King Sebastian.

John III remained neutral during the war between France and Spain, but stood firm in fighting French corsair attacks. He strengthened relations with Rome by introducing the Inquisition in Portugal and the adhesion of the Portuguese clergy to the Counter Reformation. This relationship with the Catholic Church made it possible for John to name whomever he wanted to important religious positions in Portugal: his brothers Henry and Afonso were made Cardinals, and his natural son Duarte was made Archbishop of Braga.

Commercial relations were intensified with England, the countries of the Baltic and Flanders during John's reign. Meanwhile, at the other end of the world, Portugal was the first European nation to make contact with Japan. In China, Macau was offered to the Portuguese, and soon Portugal controlled major trade routes in the area. In the South, the Portuguese continued its hostile stance against their Muslim rivals and insurgent Indian leaders. In the Moluccas John achieved an important political victory, securing the control of the area in spite of Spanish claims.

John III's support for the humanist cause was significant. In literature, his active support of Gil Vicente, Garcia de Resende, Sá de Miranda, Bernardim Ribeiro, Fernão Mendes Pinto, João de Barros and Luís de Camões was notable. In the sciences, John III supported Pedro Nunes and Garcia de Orta.

The monarch awarded many scholarships in Universities abroad (mainly in Paris), and definitively transferred the University from Lisbon to Coimbra in 1537. He quickly recalled the many prominent Portuguese born figures of European education headed by André de Gouveia, and provided the University with excellent conditions. However, the importance of the University of Coimbra was reduced by the rivalry within the advent of the Society of Jesus. The Society founded colleges and made education more widely available, but it also created great instability in Portuguese education, setting itself up as a rival of the University of Coimbra, often taking a conservative position against any innovation. The Inquisition also arrested and killed many prominent teachers and censured new ideas like Erasmism.

Another noteworthy aspect, was the support that John gave to missionaries in the New World, Asia and Africa. In 1540, after successive appeals to the Pope asking for missionaries for the Portuguese East Indies under the Padroado agreement, John III appointed Francis Xavier to take charge as Apostolic Nuncio. He had been enthusiastically endorsed by Diogo de Gouveia, who was his teacher at the Collège Sainte-Barbe and advised the king to draw the youngsters of the newly formed Society of Jesus.

The Inquisition was introduced into Portugal in 1536. As in Spain, the Inquisition was placed under the authority of the King. The Grand Inquisitor, or General Inquisitor, was named by the Pope after being nominated by the king and he always came from within the royal family. The Grand Inquisitor would later nominate other inquisitors. In Portugal, the first Grand Inquisitor was Cardinal Henry, the king's brother (who would later himself become King). There were Courts of the Inquisition in Lisbon, Coimbra and Évora and, from 1560 onwards, in Goa. The Goa Inquisition changed the demographics of Goa considerably. Goa was called the "Lisbon of the Far East" and trade reached a new level, the Portuguese did not leave Goa un-developed but progressed it to modern architecture and built strong roads and bridges which have stood the test of time even till today.

The activities of the Inquisition extended to book censorship, repression and trial for divination, witchcraft and bigamy as well as the prosecution of sexual crimes, especially sodomy. Book censure proved to have a strong influence in Portuguese cultural evolution, serving to keep the country in ignorance and cultural backwardness. Originally created to punish religious deviance, the Inquisition came to have influence in almost every aspect of Portuguese society: politically, culturally and socially.

In John III's time, trade between the Portuguese and Africans was extremely intense in the feitorias like Arguim, Mina, Mombasa, Sofala or Moçambique. "Common products were salt, wheat, horses, carpets, fabric, Irish and English clothing, blades, tin for African natives' coins, copper or tin vases, shells from the Canary Islands that Ethiopians carry on their necks as an amulet against lightning, yellow and green beads from Nuremberg, and brass armlets" (Basílio Vasconcelos, «Itinerário» de Jerónimo Münzer, 1932), in exchange for gold, slaves, ivory and bush red pepper brought by the Portuguese.

"Now, I [John III] say, like you said that there was no capture of slaves in your Kingdom [of Congo], I just want to provide you [King of the Congo] with flour and wine for your Eucharistic rites, and for that it would only be needed a caravelão [a kind of caravel] each year; if it seems right to you, in exchange for 10,000 slaves and 10,000 armlets and 10,000 ivory tooth, that, it is said, in the Congo there is not much, not even a ship per year; so, this and more shall be as you want." (Letter of John III to the King of the Congo).

Under John III, several expeditions started in coastal Africa and advanced to the interior of the continent. These expeditions were formed by groups of navigators, merchants, adventurers and missionaries. Missions in Africa were established by the College of Arts of Coimbra. The objective was to increase the king's dominion, develop peace relations and to christianize the native population.

John III refused to abandon all of the Portuguese North African strongholds, but he had to make choices:

"To want to have such a costly thing, and from which there came no profits wasn’t wise, mainly for who had so great expenditures and so huge and necessary, that cannot be stopped."

John III decided to abandon Safim and Azamor in 1541, followed by Arzila and Alcácer Ceguer in 1549. The fortresses of Ceuta, Tangiers and Mazagan were strengthened "to face the new military techniques, imposed by the generalization of heavy artillery, combined with light fire weapons and blades".

"There were years when the King had thought with his great judgement (…) to abandon the cities of Safim and Azamor (…). It was certain that Safim had no port and the river of Azamor was not navigable (…). The cost was too much that resulted in fruits of no consideration (…)".

John III declared every male subject between 20 and 65 years old recruitable on 7 August 1549.

"Every nobleman, like all my servants and those who are not, and every knight, squire, servants of mine, my brothers, and any other person that might have them [horses], I order them to have the horses ready."

Before the reign of John III, the Portuguese had already reached Siam (1511), the Moluccas (1512), the Chinese littoral (1513), Canton (1517) and Timor (1515). During John's rule, the Portuguese reached Japan, and at the end of John's reign, Macau was offered to Portugal by China.

"From India, he [John III] receives all kinds of spice, drug & stone & many cotton clothes, taficiras and alaquecas [kinds of Indian fabrics]. From Malacca, clovetrees, marzipan, sandalwood, camphor, porcelains, beijoim & calaim [kinds of spices]. From Bengala, sinafabos, flannel, chautares, castor beans, & rebotins that are kinds of thin fabric made of cotton (…). From Alexandria & Cairo, red dyewood, cinnabars, saffron, copper, rosed waters, borcados [a kind of silk], velvets, taffeta, grains of wood, camlets, gold & silver in bars, & in coins, & carpets. From China, musk, rhubarb, & silk in exchange of gromwells, pearls, horses from Arabia & Persia, non worked silk, silk embroidery threads, fruits of the date palm, raisins, salt, sulphur & many other goods." (Fernão Lopes de Castanheda, História do Descobrimento e Conquista da Índia pelos Portugueses, 1979)

As Muslims and other peoples constantly attacked Portuguese fleets in the area, and because India was so far from mainland Portugal, it was extremely difficult for John III to assure Portuguese dominion in this area. A Viceroy, a Governor General with extensive powers, was nominated, but it was not enough. The Portuguese started by creating feitorias – commercial strongholds (Cochin, Cannanore, Coulão, Cranganore and Tanor) – with the initial objective of establishing just a commercial dominion in the region.

The hostility of many Indian kingdoms, and the alliances between sultans and zamorins to expel the Portuguese, made it necessary for the Europeans to establish a sovereign state. So, Portugal militarily occupied some key cities on the Indian coast, and Goa (1512) became the headquarters of the Portuguese Empire in the East. Goa became a starting point for the introduction of European cultural and religious values in India, and churches, schools and hospitals were built. Goa remained an overseas possession of Portugal until India reclaimed it in 1961.

The Portuguese arrived in Japan in 1543. Japan was known to Portugal since the time of Marco Polo, who called it Cipango. Whether Portuguese nationals were the first Europeans to arrive in Japan is debatable. Some say it was the writer Fernão Mendes Pinto, and others say the navigators António Peixoto, António da Mota and Francisco Zeimoto.

Portuguese traders started negotiating with Japan earlier than 1550, and established a base there at Nagasaki. By then, trade with Japan was a Portuguese monopoly, under the rule of a Captain. Because the Portuguese established themselves in Macau, Chinese commercial relations, mainly the silver trade with Japan, were improved under John III's rule.

After the voyage of Ferdinand Magellan, the Castilians claimed the recently discovered Moluccas Islands. In 1524, a conference of experts (cartographers, cosmographers, pilots, etc.) was held to solve the dispute caused by the difficulty of determining the meridian agreed to in the Treaty of Tordesillas. The Portuguese delegation sent by John III included names such as António de Azevedo Coutinho, Diogo Lopes de Sequeira, Lopo Homem and Simão Fernandes. The dispute was settled in 1529 by the Treaty of Zaragoza, signed by John III and Charles I of Spain. The Portuguese paid 350,000 golden ducados to Spain and secured their presence in the islands. This payment should not have been a necessity, as Portugal was actually entitled to the islands, according to the Treaty of Tordesillas.

In 1553, Leonel de Sousa obtained authorization for the Portuguese to establish, in Canton and Macau. Macau was later offered to John III as a reward for the Portuguese assistance against maritime piracy in the period between 1557 and 1564.

"In the morning of the other day, we set sail from this island of Sanchão and when the sun set, we arrived at another island, that lies six more leagues to the north, called Lampacau, where at that time the Portuguese made trade with the Chinese, and they made it until the year of 1557, when the mandarins of Canton, when asked by Portuguese land merchants, gave this port of Macau to us (…)." (Fernão Mendes Pinto, Pilgrimage, 1974 ed.)

Portugal retained Macau for over 400 years. It became a Special Administrative Region of the People's Republic of China in 1999, two years after Hong Kong was similarly returned to Chinese jurisdiction by the UK.

Malacca, which controlled the eponymous Strait of Malacca, was vital to Portuguese interests in the Far East. After an unsuccessful expedition in 1509, Malacca was finally conquered by Afonso de Albuquerque, the Portuguese viceroy of India, on 24 August 1511. Malacca was later taken by the Dutch in 1641.

In order to follow its trade routes to the Far East, Portugal depended on the seasonal monsoon winds in the Indian Ocean. In winter, the prevailing northeasterly monsoon impeded travel to India; in summer, the southwest monsoon made departure from India difficult. As a result, Portugal determined that it needed permanent bases in India, in addition to its ports of call in Africa, to pass the time while the wind changed. In addition to Goa, they founded a base at Colombo (in what is now Sri Lanka) in the sixteenth century. This port remained in Portuguese hands until 1656, when it was seized by the Dutch after an epic siege.

Immediately following the discovery of Brazil, the Portuguese imported brazilwood, Indian slaves and exotic birds from there. Brazilwood was a much appreciated product in Europe, because it could be used to produce a red dye. During John III's rule, after the initial colonization, Portuguese explorers intensified the search for brazilwood and began the cultivation of sugarcane which was well suited to the climate of Brazil, especially around Recife and Bahía. Since Brazil lacked a large native population, and the Indians did not make good plantation workers, the Portuguese colonists began to import African slaves to work their plantations. The first slaves, from the region of Guinea, arrived in Brazil in 1539. Most of them worked in the sugarcane fields or were house servants.

John III was the first Portuguese monarch to recognize the potential of the New World, and the colonization of Brazil began during his reign. The territory was divided into 12 captaincies in 15 lots (some captaincies had more than one lot) that were given to donatary captains with obligations to defend them, populate them, and to develop their resources.

"Martim Afonso, my friend, I, the King (…) knew of your arrival at this land of Brazil, and because of your patrol of the coast (…) against the French corsairs, (…) I thank you (…). After you left, a question was raised if it would be my service to populate all that coast of Brazil, and some people asked me for captaincies (…), so I ordered to mark from Pernambuco to the Rio da Prata [Río de la Plata] fifty leagues of coast to each captaincy, and before giving them to anyone, I ordered a hundred of the best leagues of the coast to be marked to you and fifty leagues to your brother, Pêro Lopes (…). I also gave captaincies of fifty leagues to some people (…) and everyone is willing to take people and ships with them (…)" (Letter of John III to Martim Afonso de Sousa)

The first Governor General appointed by John III was Tomé de Sousa, who in 1549 founded the city of Bahia (known at the time as São Salvador da Bahia de Todos os Santos - Holy Saviour of the Bay of All Saints).

From 1539, the heir to the throne was John, prince of Portugal, who married Joan of Spain, daughter of Charles V. But Prince John was a sickly child (and the sole son of John III to survive childhood) and died young (of juvenile diabetes), eighteen days before the princess gave birth to Prince Sebastian on 20 January 1554. When John III died of apoplexy in 1557, only heir was his grandson, Sebastian, who was just three years old.

Today, John's body rests in the Monastery of Jerónimos in Lisbon.