Isabella I of Castile Biography

(Former Queen of Castile and Leon (1474 - 1504))

Birthday: April 22, 1451 (Taurus)

Born In: Madrigal de las Altas Torres, Spain

Isabella I was the Queen of Castile and after her husband Ferdinand II became the King of Aragon, Isabella became the Queen consort of Aragon. Marriage of the royal couple laid foundation for political unification of Spain and although Castile and Aragon remained de jure two different kingdoms till Philip V of Spain signed the Nueva Planta Decrees of 1716, Isabella and Ferdinand are respectively considered the first de facto Queen and King of Spain. Isabella reorganized the governmental system in Castile, unburdened the huge debt left by her predecessor, and substantially decreased crime rate of the kingdom. The royal couple gained repute for finishing the Reconquista, emerging victorious in the Granada War against Nasrid dynasty's Emirate of Granada leading to end of all Islamic rules on the Iberian peninsula and annexation of Granada by Castile. This victory of the Christians led Pope Alexander VI to award the couple the title of Catholic Monarchs. The Catholic Church later recognized her as a Servant of God. The royal couple also sponsored first voyage of Christopher Columbus in 1492 when the latter independently discovered the Americas and magnetic declination.

Quick Facts

Spanish Celebrities Born In April

Also Known As: Isabella I, Queen of Spain

Died At Age: 53


Spouse/Ex-: Ferdinand II of Aragon (m. 1469)

father: John II of Castile

mother: Isabella of Portugal

siblings: Alfonso;Prince of Asturias, Catherine; Princess of Asturias, Eleanor; Princess of Asturias, Henry IV of Castile, María de Castilla

children: Catherine of Aragon, Isabella of Aragon; Queen of Portugal, Joanna of Castile, John; Prince of Asturias, Maria of Aragon

Born Country: Spain

Empresses & Queens Spanish Men

Died on: November 26, 1504

place of death: Medina del Campo, Spain

Ancestry: English Spanish, Portuguese Spanish

Early Life, Marriage & Ascension as Queen of Castile & León

Isabella was born on April 22, 1451, in Madrigal de las Altas Torres, Ávila, to the King of Castile and León, John II of Castile, and his second wife, Isabella of Portugal.

At the time of her birth Isabella’s older half-brother Henry IV of Castile was the heir apparent and she was second in line to the throne, and following birth of her younger brother Alfonso of Castile in 1453, she became third in line to the throne.

John II died in 1454, following which Henry ascended as King Henry IV of Castile. Isabella and Alfonso were virtually exiled to Segovia and their mother to Arevalo. The siblings were later moved to Henry's court at Madrid and were placed in the household of Henry’s wife, Queen Joan.

Dissatisfied with rule of Henry, the noblemen began a civil war in Castile in 1464 and eventually demanded that Alfonso be named successor of Henry. Henry had to repudiate his daughter Joanna and recognize Alfonso as heir presumptive and grant him the title of Prince of Asturias.
Alfonso suddenly died on July 5, 1468, probably of the plague, although rumours of a possible poisoning and slit throat also did the rounds. The rebellious nobles then turned to Isabella who was named as Alfonso’s successor to the crown in the latter’s will.
Isabella preferred to negotiate with Henry leading to the September 19, 1468, Treaty of the Bulls of Guisando, according to which Isabella was granted the title of Princess of Asturias. She became heiress presumptive to the Crown of Castile and was to marry only with the consent of Henry. Henry’s daughter Joanna was removed from the line of succession to the throne.
Isabella married Ferdinand, the younger son of John II of Navarre, who hailed from a cadet branch of the House of Trastámara, on October 19, 1469, in Valladolid, Kingdom of Castile and Leon. This infuriated Henry who shunned the Treaty and once again recognized the rights of his daughter Joanna in a ceremony.
Although later Isabella and Henry reconciled to some extent, following Henry’s death and ascension of Isabella as the Queen of Castile and León on December 11, 1474, the War of the Castilian Succession broke with Joanna being backed by Portugal and Isabella by Aragon.

Initially France backed Joanna, however following the March 1, 1476, Battle of Toro, France refused to help Joanna and signed a peace treaty with Isabella in 1478.

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Marriage of Ferdinand and Isabella included a premarital agreement on sharing of power with the joint motto ‘tanto monta, monta tanto’. After Isabella became Queen Isabella I of Castile, Ferdinand became the jure uxoris King of Castile and the couple ruled as co-monarchs.
Isabella took strict measures in regulating crime bringing its rate to the lowest it had been in years. The couple established a centrally organized and efficient Holy Hermandad (Santa Hermandad) for Castile, Leon, and Asturias in 1476 and gave it great powers to regulate crime. Isabella also restored finances of the crown and unburdened the kingdom of the huge debt that was left by Henry.
In 1478, Ferdinand and Isabella, jointly known as the Catholic Monarchs, established the Tribunal of the Holy Office of the Inquisition, generally called the Spanish Inquisition. Its objective was to maintain orthodoxy of Catholicism in their kingdoms replacing the Medieval Inquisition.
Ferdinand’s father died on January 20, 1479, after which Ferdinand inherited the crown of Aragon. This resulted in unification of different territories of the kingdoms of Castile and Aragon in a personal union. Although under the same crown, the different states were administered as separate political units.
Early years of joint reign of Isabella and Ferdinand witnessed several military campaigns, better known as the Granada War, between 1482 and 1491, against the Nasrid dynasty's Emirate of Granada. The war ended on January 2, 1492, with victory of the Catholic Monarchs marking not only annexation of Granada by Castile but also end of all Islamic rules on the Iberian Peninsula.

On March 31, 1492, the couple issued an edict called the Alhambra Decree, also referred as Edict of Expulsion ordering expulsion of Jews from the Kingdoms of Castile and Aragon if they refuse to baptise and convert to Christianity. The edict allowed converso Marrano Jews and Mudéjar Moors (Islamic) to remain in the kingdoms.

The first European expedition of Christopher Columbus that started on August 3, 1492, was sponsored by the royal couple. Thus, the Catholic Monarchs played an instrumental role in initiating the first European encounters in the future Americas.
On June 7, 1494, the Treaty of Tordesillas was signed that saw division of the newly discovered lands beyond Europe between the Crown of Castile and the Portuguese Empire.
Isabella issued a decree in 1500 and granted citizenship and full legal freedom to all non-rebellious natives in the colonies.
Family, Death, Succession & Legacy
Isabella had seven children with Ferdinand including Isabella, Queen of Portugal; John, Prince of Asturias; Joanna, Queen of Spain; Maria, Queen of Portugal; and Catherine, Queen of England.
Isabella was overwhelmed by her family tragedies in her later life which included death of her children John in 1497 and Isabella in 1498. On September 14, 1504, Isabella withdrew from governmental affairs and died on November 26, 1504. She was buried in the Royal Chapel of Granada. According to her will dated October 12, 1504, her daughter Joanna became Queen of Castile while Ferdinand proclaimed himself Governor and Administrator of Castile. As per the will, after Joanna, her son Charles would succeed the crown of Castile.
In June 1506, Ferdinand, and Joanna‘s husband Philip the Handsome, signed the Treaty of Villafáfila that recognised incapacity of mentally unstable Joanna to rule Castile on her own. Ferdinand ceded all power of the government of Castile to Philip who was proclaimed Philip jure uxoris King of Castile. After Philip’s death Ferdinand ruled as regent until his own death.
Joanna’s son Charles became co-monarch of Spain with her on March 14, 1516, however Joanna remained imprisoned until her death. Charles inherited the Crown of Castile and the Crown of Aragon and emerged as the first king to rule the two kingdoms Suo jure and simultaneously as a united Spain, for which he is generally referred as the first king of Spain.
The Order of Isabella the Catholic was created in 1815 honouring Isabella. In March 1974, she was given the title "Servant of God". She became the first woman to feature on US postage stamps and first named woman to feature on US coin.

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