Alonso de Fonseca y Ulloa

Alonso de Fonseca was a Castilian prelate and political figure who played a significant role in governing the Kingdom of Castile during Henry IV's reign. Born into a prominent family of Portuguese origin, he pursued an ecclesiastical career under the patronage of influential relatives. He held major offices, including Bishop of Ávila, Archbishop of Seville and Archbishop of Santiago de Compostela. Closely associated with the royal court from his early service to the future king, he became a member of the royal council and a key intermediary in political negotiations among competing noble factions. His career included periods of influence and setbacks, especially during conflicts involving Juan Pacheco and the civil strife of the 1460s, where he often acted as a mediator. He participated in major political settlements, including the Treaty of the Bulls of Guisando. He helped consolidate royal authority while advancing his family's interests through ecclesiastical appointments. In later years, his activity declined due to illness, and he died at Coca in 1473. He was also noted for his patronage of learning and the arts, maintaining a substantial library and supporting contemporary scholars.