Leonor of Portugal (1434-1467) was a Portuguese princess and the daughter of King Edward of Portugal and Leonor of Aragon. She became the Queen of Castile through her marriage to King John II of Castile in 1455, which strengthened the ties between Portugal and Castile. As queen, Leonor played a significant role in the political landscape of the Iberian Peninsula. Her marriage helped to solidify alliances and foster cooperation between the two kingdoms during a time of political intrigue and conflict. Leonor's legacy is often associated with her contributions to the royal court and her influence on her husband's reign.