Fernando II of Aragon, also known as Ferdinand the Catholic, was born on March 10, 1452. He became King of Aragon in 1479 and is best known for his marriage to Isabella I of Castile, which united the two largest kingdoms in Spain. This union laid the foundation for the modern Spanish state. Ferdinand played a crucial role in the completion of the Reconquista, the campaign to reclaim the Iberian Peninsula from Muslim rule, culminating in the capture of Granada in 1492. He also sponsored Christopher Columbus's voyage, leading to the discovery of the Americas.