John III of Portugal

John III of Portugal, known as "the Pious," ruled as King of Portugal and the Algarve from 1521 until his death in 1557. Born on 6 June 1502, he was the eldest son of King Manuel I and his second wife, Maria of Aragon, who was herself the third daughter of Spain’s Catholic Monarchs, Ferdinand and Isabella. John took the throne at nineteen, following his father’s death.

His reign saw the Portuguese Empire grow significantly, with new territories in Asia and the Americas, especially through the colonization of Brazil. By strengthening key bases in India—most notably Goa—John secured Portugal’s control over the lucrative spice trade in cloves and nutmeg from the Maluku Islands. When he died on 11 June 1557, the empire covered nearly 4 million square kilometres.

Under John, the Portuguese became the first Europeans to make contact with Japan during the Muromachi period. He also chose to abandon several Muslim-held outposts in North Africa, redirecting focus toward trade with India and investment in Brazil. In Europe, he worked to improve relations with the Baltic region and the Rhineland, hoping to boost Portuguese commerce.

John was born in Lisbon, and his birth was celebrated with a performance of Gil Vicente’s *Visitation Play* in the queen’s chamber. He was formally recognized as heir to the throne in 1503, the same year his sister Isabella—later Empress of the Holy Roman Empire—was born. His education came from notable scholars, including the astrologer Tomás de Torres, Bishop Diogo de Ortiz, and the humanist Luís Teixeira Lobo, who taught him Latin, Greek, mathematics, and cosmography. According to his chronicler António de Castilho, John handled problems easily, making up for any lack of formal learning with practical experience. He was given his own household in 1514 and soon began assisting his father with administrative duties.

At sixteen, John was meant to marry his first cousin, Eleanor of Austria, but she instead wed his widowed father, Manuel. This deeply upset John, leaving him melancholic, and some historians believe it contributed to his later intense religiosity, which earned him the nickname “the Pious.”

John was crowned on 19 December 1521 in Lisbon’s Church of São Domingos, beginning a 36-year reign focused on both domestic and overseas affairs. He continued the absolutist policies of his predecessors, summoning the Portuguese Cortes only three times: in 1525, 1535, and 1544. Early in his rule, he also tried to reform the kingdom’s administration and judiciary.

His sister Isabella’s marriage to Holy Roman Emperor Charles V helped strengthen ties with Spain and the empire. John himself married Catherine of Austria, Charles’s younger sister and his own maternal first cousin, in Crato. The couple had nine children, but all died young; by John’s death, only his grandson Sebastian survived to inherit the throne.

The sprawling Portuguese Empire was costly and difficult to govern, burdened by heavy debt and trade deficits. In Asia, poor administration by ambitious governors led to chaos, and new appointees often had to fight their predecessors just to take office. This decline gradually weakened Portugal’s trade monopoly. Facing military pressures worldwide, John declared in 1549 that all men aged 20 to 65 could be recruited for service. His colonial governors in Asia included Vasco da Gama, Pedro Mascarenhas, Nuno da Cunha, and João de Castro, among others.

The empire faced threats from the Ottoman Empire in both the Indian Ocean and North Africa, forcing Portugal to spend heavily on defenses. In the Atlantic, French privateers and an attempted French colony in Brazil—France Antarctique—added another front, with the French allying with indigenous peoples against the Portuguese. The French were eventually expelled, but not until 1565.

In the early years of John’s reign, exploration in the Far East continued, reaching China and Japan. But these gains were offset by the growing power of the Ottoman Empire under Suleiman the Magnificent, especially in India, where attacks became more frequent. To fund the costly defense of Indian interests, John abandoned several North African strongholds, including Safim, Azemmour, Ksar es-Seghir, and Arzila.