John's birth helped consolidate Isabella's position as a sovereign.[3] At the time of his birth, he had one elder sister Isabella;[4] his younger sisters were Joanna, Maria, and Catherine.[5]
The Catholic monarchs won the war against the King and Queen of Portugal.[6] To negotiate a peace settlement with Isabella, King Afonso sent Infanta Beatrice, Duchess of Viseu. The two women met in March 1479.[7] Beatrice was Afonso's sister-in-law and Isabella's maternal aunt. By terms of the treaty they eventually negotiated, the former Queen of Portugal (her marriage having been annulled by the Pope) was given two options: she could either wed Prince John, waiting 13 or 14 years until the prince was old enough to be married (by which time Joanna herself would be at least thirty) or she could enter a convent; either way she was to give up her claim to the throne.[8][9]
Childhood
Isabella I was quite an attentive mother for such a busy queen.[10] John, being her only son and of delicate health, had a special place in her heart,[11][12] and she referred to him affectionately as 'my angel' even when he was being reprimanded by her.[13] Isabella and Ferdinand attempted to ensure the sickly prince's well-being through prayer, charity, and careful oversight of his health.[14][15] John's wetnurses were Maria de Guzman, a member of the powerful Spanish House of Mendoza,[12] and Juana de Torres.[16] The latter stayed by the prince's side well into his adolescence, possibly as a result of his frail health.[17]
John's paternal grandfather, King John II of Aragon, took close interest in the infant prince; he warned his son Ferdinand that the prince should not be tutored under one grandee, a member of the nobility, as they would have far too much influence over the boy.[12]
In 1492, Columbus named the newly discovered island of Cuba as Isla Juana in deference to Prince John, at that time the heir apparent.[18] In 1494, Columbus's sons, Diego and Ferdinand, were brought to court to serve as John's pages.[19]
Education
John, Prince of Asturias, as the sole male heir of the Catholic Monarchs, Ferdinand II of Aragon and Isabella I of Castile, received a rigorous education tailored to prepare him for his future role as a ruler.[20] His education reflected the high expectations placed on him as the heir to two of Europe’s most powerful thrones. It combined traditional religious and moral instruction with the progressive influence of Renaissance humanism, emphasizing religious, moral, and intellectual development, in line with the values of his parents and the responsibilities he was expected to inherit.[21]
In 1492, Queen Isabella expanded John’s education by appointing the Italian humanist Peter Martyr d'Anghiera as his personal tutor.[22] Under Martyr's tutelage, John excelled in philosophy, theology, and the liberal arts.[23] Martyr introduced the prince to the principles of humanism, broadening his education to include classical studies and civic virtues. This reflected the Renaissanceideals spreading across Europe, marking a shift from purely religious instruction to a more rounded educational approach. Nonetheless, his education remained deeply rooted in traditional Christian values, influenced by the deeply Catholic nature of his parents' reign.[20]
When John was 13 years old, Isabella invited the sons of aristocrats, including future notable figures such as Nicolás de Ovando y Cáceres and Gonzalo Fernández de Oviedo y Valdés, to live at the royal court. This arrangement was designed to prevent John from becoming coddled or willful by surrounding him with peers who could serve as role models and companions. These young nobles were educated alongside John, receiving instruction in noble virtues and Christian values to ensure they were well-prepared for their future roles in court and beyond.[24]
John’s daily routine reflected the structured nature of his upbringing. His mornings began with dressing and grooming by attendants, followed by prayer and religious study under his preceptor’s supervision. After attending Mass, he spent an hour on academic lessons. Afternoons were reserved for physical activities such as riding, jousting, and hunting, considered essential skills for a prince.[23] John also demonstrated a talent for music, mastering instruments like the flute and clavichord, which earned him admiration at court. His musical abilities were not merely for personal enjoyment; they also played a role in his public image, showcasing his refinement and cultural sophistication—a valued trait in Renaissance courts across Europe.[23]
Despite the comprehensive nature of his education, John's delicate health posed significant challenges.[12] His frailty likely influenced the pace and intensity of his studies, as his tutors had to balance rigorous training with the reality of his physical limitations. This delicate balance was a constant concern for his parents, who were deeply invested in ensuring that their only son was well-prepared to unify the crowns of Aragón and Castile, despite the ever-present threat of his declining health.[20]
In 1494, King Charles VIII of France laid claim to the throne of Naples and launched an invasion of Italy. Because Naples belonged to a lesser branch of the House of Trastámara, his invasion directly threatened Aragonese interests.[27] This prompted King Ferdinand to began building a coalition, known as the Holy League, against France.[28] Seeking Emperor Maximilian I's participation, Ferdinand engaged in negotiations for dynastic marriages between the Habsburg and Spanish royal families, aiming to seal the prospective alliance between the Holy Roman Empire and Spain.[29]
On 20 January 1495 in Antwerp, terms for a double marriage were agreed on: John would marry Maximilian I's daughter, Archduchess Margaret of Austria, and his sister, the Infanta Joanna, would marry Maximilian's son, Archduke Philip the Handsome.[30][31] The agreement was officially ratified on 5 November in Malines.[32]
Marriage
Infanta Joanna sailed from Spain to marry Philip the Handsome in late 1496, accompanied by a grand fleet. The same fleet returned months later carrying Philip's sister, Margaret of Austria.[33] Margaret, aged sixteen, had already been betrothed once to Charles VIII, but the marriage treaty was renounced.[34] Her engagement to the Prince of Asturias seemed doomed when the ship carrying her to Spain hit a storm in the Bay of Biscay.[35] In haste, she wrote her own epitaph should she not reach Spain.[36]
"Here lies Margaret, the willing bride, Twice married – but a virgin when she died."
However, Margaret arrived in Spain safely and married Prince John on 3 April 1497 in Burgos Cathedral.[37] Although the marriage was a political one, the young couple quickly became devoted to each other.[38] Apparently, the amount of time they spent in bed made the court physicians uneasy about the Prince's health.[37]
Death
In September 1497, John's fragile health prevented him from joining his parents and sister, Infanta Isabella, as they journeyed to the Portuguese border for her wedding to Manuel I.[38] Instead, he and Margaret travelled to Salamanca, marking their arrival with a ceremonial entry.[39] The next week, after receiving reports that John's condition was worsening, Ferdinand rushed to his son's bedside.[40]
On 4 October 1497, John died,[41] possibly of tuberculosis[42] or smallpox.[a] His dog, a lurcher called Bruto, had whimpered as he died, then stayed next to his coffin throughout the vigil in Salamanca's main church.[44] John's devastated mother would later keep the dog next to her, as if to keep the memory of her beloved son with her.[45] Six months later, on 2 April 1498, the Princess of Asturias gave birth to their only child, a stillborn girl.[46]
Consequences
John's death was followed closely by that of his sister Isabella in 1498.[47] Her only child, Miguel de la Paz, died in 1500.[48] The Spanish kingdoms passed to his younger sister Joanna, her husband Philip the Handsome, and their Habsburg descendants.[31] Philip had himself and Joanna declared as 'Princes of Castile' which her parents saw as disrespectful towards his deceased brother-in-law.[45]
^ abOrtega Gato, Esteban (1999). "Los Enríquez, Almirantes de Castilla" [The Enríquezes, Admirals of Castille] (PDF). Publicaciones de la Institución "Tello Téllez de Meneses" (in Spanish). 70: 42. ISSN0210-7317.
Sánchez, Margarita (11 May 2018). "La muerte del príncipe Don Juan. Exequias y duelo en Córdoba y Sevilla durante el otoño de 1497" [The Death of Prince Juan. Funeral Rites and Mourning in Cordoba and Seville during the Autumn of 1497]. Espacio Tiempo y Forma. Serie III, Historia Medieval. Universidad Nacional de Educacion a Distancia: 107–133. doi:10.5944/etfiii.31.2018.21137.