تاريخ إسبانيا
Bilbao Azkarreta's secondary education was at least partly at the Jesuit college in Bilbao. In 1932 obtained the degree of Bachelor of Science at the University of Valladolid. Between 1932 and 1936 he attended the Universidad Central de Madrid, pursuing studies in Philosophy and Literature, specializing in History. He took a degree in Medieval History of Spain with Latin and Arabic as the language requirements. He then returned to Bilbao, where there were plans to open a Basque University, but after the outbreak of the Spanish Civil War he enrolled with the "Eusko Gudarosteak" (Basque Battalions) as a lieutenant of engineers, serving 1936-1937.