Ferdinand I of León

Ferdinand I (c. 1015–1065), called the Great, was a younger son of Sancho III of Pamplona. Count of Castile from 1029, he married Sancha of León and in 1037 killed Bermudo III at Tamarón, taking the crown of León in 1038.

He had acknowledged the supremacy of his elder brother García of Navarre, but in 1054 defeated him at Atapuerca, where García was killed. Tradition holds that Ferdinand was crowned emperor of Spain in 1056.

He extracted tribute from the Muslim taifas and took Coimbra in 1064. He died in December 1065, leaving Castile, León and Galicia to his sons Sancho, Alfonso and García.