Queen Isabella I of Castile, who reigned alongside her husband Ferdinand II of Aragon, had a total of five children. Their names were:
- Isabella, later known as Isabella of Spain
- John, who became the Prince of Asturias
- Juana, often referred to as Juana the Mad
- Maria, who would go on to marry into the Portuguese royal family
- Catherine, who married Henry VIII of England
Isabella’s children played significant roles in unifying Spain and furthering the influence of the Spanish monarchy in Europe through various dynastic marriages. Their lives and unions were an essential part of the strategy that helped lay the foundations for Spain as a major world power during the Age of Exploration.