Isabella I of Castile

Isabella I was Queen of Castile from 1474 until she died in 1504, reigning over a dynastically unified Spain jointly with her husband, King Ferdinand II of Aragon. She was Queen of Aragon after Ferdinand ascended in 1479. Together they are known as the Catholic Monarchs.After a struggle to claim the throne, Isabella reorganized the governmental system, brought the crime rate to the lowest it had been in years, and unburdened the kingdom of the enormous debt her brother had left behind. Isabella's marriage to Ferdinand in 1469 created the basis of the de facto unification of Spain. Her reforms and those she made with her husband had an influence that extended well beyond the borders of their united kingdoms.

Isabella and Ferdinand are known for completing the Reconquista, ordering the expulsion of Muslims and Jews from Spain, for supporting and financing Christopher Columbus's 1492 voyage that led to the discovery of the New World by Europeans, and for the establishment of Spain as a…

Source: Wikipedia