Isabella I (1451–1504) was queen of Castile and León. She and her husband Ferdinand II of Aragon brought stability to both kingdoms that became the basis for the political unification of Spain under their grandson Charles V, the Holy Roman Emperor. Along with the physical unification of Spain, Isabella and Ferdinand were major players in the Counter-Reformation and embarked on a process of spiritual unification, trying to bring the whole of Spain under one faith (Roman Catholicism). As part of this process, the Inquisition became institutionalised and they embarked on what would today be termed a massive programme of ethnic cleansing; the Pope rewarded them by granting them the title of Catholic Monarchs.
1492 was an important year for Isabella: the conquest of Granada and hence the end of the Reconquista; her successful patronage of Christopher Columbus; and her expulsion of Jews and Muslims from Spain.
In January 1492, after a ten year campaign, Isabella and Ferdinand entered Granada, the last of the Taifa states, to receive the keys of the city and completed the Reconquista. Although the principal mosque was reconsecrated as a church the Treaty of Granada assured religious rights to the Muslims. The Treaty of Granada was abrogated in 1502 and Muslims were forced to either be baptised or to be expelled.
In March 1492, the Alhambra Decree for the expulsion of the Jews was issued at the instigation of Tomás de Torquemada, the first Inquisitor General. Some 200,000 left Spain; others converted, but often came under scrutiny by the Inquisition investigating relapsed conversos (Marranos) and the Judaizers who had been abetting them. The Muslims of the newly conquered Granada had been initially granted religious freedom, but pressure to convert increased, and after some revolts, a policy of forced expulsion or conversion was also instituted in 1502.
In August 1492 Christopher Columbus set sail for the Indies. Queen Isabella had rejected Christopher Columbus’s plan to reach the Indies by sailing West more than three times before changing her mind. In 1494, by the Treaty of Tordesillas, Isabella and Ferdinand agreed to divide the Earth, outside of Europe, with king John II of Portugal.
Isabella was of a very fair complexion and had the blue eyes, and had a reddish-blonde to auburn hair colour that were typical in members of the Trastámara family. Isabella died in 1504 in Medina del Campo and was buried in Granada.