Queen Isabella I of Castile – The early years of Isabella

The future Queen Isabella I of Castile was born on 22 April 1451 as the eldest child of King John II of Castile and his second wife, Isabella of Portugal.

From his first marriage, her father had one surviving son, the future King Henry IV. He was 26 years older than his newborn half-sister. Nevertheless, a second son would have been preferred, and a brother named Alfonso followed on 17 November 1453. With two brothers ahead of her in the succession, Isabella was not expected ever to become Queen.

Isabella probably had little memory of her father, as he died on 20 July 1454 when she was just three years old. Her older half-brother Henry now became the new King. Isabella, her mother and brother moved to Arévalo, where they lived in a two-story house. The town was known for its clean air, and “the plague was rarely known here.”¹ For her mother, these were dark days, and she reportedly shut herself “in a dark room, condemning herself to silence.”² They were soon joined in Arévalo by Isabel of Barcelos, young Isabella’s maternal grandmother. It was Isabel of Barcelos who oversaw Isabella’s early childhood and education. Isabella also became close to her brother, Alfonso.

It is not entirely clear what kind of education Isabella received, but she certainly received the usual female training in domesticity. She learned to speak Portuguese, and she rode horses. The family spent quite a few quiet years at Arévalo, but as King Henry’s wife Joan came close to giving birth, Henry wanted any potential challengers for the throne kept close by. The ten-year-old Isabella and seven-year-old Alfonso were recalled to court. Isabella later wrote, “Alfonso and I, who were just children at the time, were inhumanely and forcibly torn from our mother’s arms and taken into Queen Juana (Joan)’s power.”³

Isabella and Alfonso said goodbye to their mother and grandmother at the end of 1461 to travel to the court at Segovia. They went from childhood innocence to a court full of intrigue. Isabella learned quickly about courtly love and its limits. Isabella moved into the Queen’s household, which was separated from the King’s side by an animal house that housed lions. She probably saw very little of her half-brother. As the Queen’s due date neared, she was moved to the Alcazar palace in Madrid, and Isabella joined her there. On 28 February 1462, the Queen gave birth to a daughter – Joanna. Isabella acted as godmother for her newborn niece.

Joanna was their first child after seven years of marriage and would prove to be the only surviving child. However, it appears that several nobles already doubted Joanna’s legitimacy, not in the least because of jealousy towards Beltrán de la Cueva, who held the King’s favour. It is impossible to tell if Joanna was Beltrán de la Cueva’s daughter, but we know Joan conceived again within the year. Tragically, she lost the child, a boy, at six months.

Three months later, Henry had Joanna sworn in as the heiress to the throne, and Isabella and her brother Afonso were the first ones to swear. Isabella later claimed that she knew why some nobles said that they had sworn against their will. She wrote, “It was something she [the Queen] had demanded because she knew the truth about her pregnancy and was taking precautions.”⁴

Nevertheless, the allegations surrounding Joanna’s paternity were the perfect breeding ground for a rebellion.

Joanna was just two years old when a manifesto of complaints and grievances was issued against King Henry by several nobles. This led to the Representation of Burgos in 1464, where Henry was forced to recognise Alfonso as the legitimate heir.⁵ This was agreed upon with the condition that Alfonso would one day marry Joanna. However, Henry soon reconsidered, and this led to a ceremonial deposition in effigy in 1465, and the 11-year-old Alfonso was crowned as rival King. Meanwhile, Isabella was still at court with Henry and Joan.

After turning 12 in 1463, Isabella became a piece of the marriage chessboard. Her half-brother, King Henry IV, sought the support of Portugal while the nobles of Castile leaned towards Aragon. Sometime in April 1464, Isabella found herself on the way to the Portuguese border to meet with the 31-year-old King Afonso V of Portugal. However, this marriage did not take place.

In 1466, one of the rebels suggested a marriage with Isabella as the best way to get his family’s loyalty back. In this plan, Isabella was to marry Pedro Girón Acuña Pacheco, who was also 18 years her senior. Henry agreed to the match, but Isabella was horrified as she considered this match to be beneath her dignity. She sank to her knees and began to pray, begging God to free her from the match. As he rode towards the court, he fell ill and died, much to Isabella’s relief.

Isabella and Alfonso were reunited in 1467 when he triumphantly rode into Segovia as Queen Joan fled. She later wrote, “I stayed in my palace, against the queen’s will, in order to leave her dishonest custody that was bad for my honour and dangerous for my life.”⁶ She made Alfonso’s counsellors sign a document stating that she would not be forced into marriage before agreeing to come with them.

Isabella also asked to return to her mother at Arévalo, and at the end of the year, they celebrated Alfonso’s 14th birthday with the three of them. They stayed there until they were forced to flee due to an outbreak of the plague at the end of June 1468. Alfonso fell ill at Cardeñosa, and for four days, he fought for his life. His death was expected, and Isabella wrote, “And you all know that in the moment that the Lord decided to take his life, succession of the kingdoms and royal lands of Castile and Leon will, as his legitimate heiress and successor, pass to me.”⁷

Alfonso died on 5 July 1468. The battle was now between Joanna and Isabella.

1. Isabella of Castile: Europe’s First Great Queen by Giles Tremlett p.19
2. Isabella of Castile: Europe’s first Great Queen by Giles Tremlett p.19
3. Isabella of Castile: Europe’s First Great Queen by Giles Tremlett p.25
4. Isabella of Castile: Europe’s First Great Queen by Giles Tremlett p.32
5. Due to male-preference primogeniture, Isabella was behind Alfonso in the line of succession
6. Isabella of Castile by Giles Tremlett p.39
7. Isabella of Castile by Giles Tremlett p.40