Queen Isabelle, also known as Isabella I of Castile, was a significant figure in Spanish history. Born in 1451, she became Queen of Castile in 1474 and ruled alongside her husband, Ferdinand II of Aragon. Together, they unified Spain and completed the Reconquista, which ended Muslim rule in the Iberian Peninsula. Isabelle is also known for sponsoring Christopher Columbus's 1492 voyage, which led to the discovery of the Americas. Her reign marked the beginning of Spain's rise as a global power, and she played a crucial role in establishing the Spanish monarchy's authority and influence during the late 15th century.