In this paper we reconstruct little-know aspects about the biography of the Spanish medievalist Claudio Sánchez-Albornoz (1893-1984). At the same time, we analyse the personal causes and the historical circumstances that led one of the most important Spanish historians from the first half of the 20th century to emigrate to Buenos Aires, and in what way that experience resulted in the foundation of the Cuadernos de Historia de España. We highlight the intellectual and historiographic significance of this foundation for Hispanic medievalism. [ABSTRACT FROM AUTHOR]