Juderías, who worked at the Spanish Embassy in Russia, had noticed (and denounced) the spread of anti-Russian propaganda in Germany, France and England and was interested in its possible long-term consequences. Juderías was the first historian to describe the "black legend" phenomenon, and identified its Spanish counterpart. His 1914 book, La Leyenda Negra y la Verdad Histórica (The Black Legend and Historical Truth), deconstructs aspects of Spain's image (including those in Foxe's Book of Martyrs).