The Pavelló de la República Library joined what is now the University of Barcelona's Learning and Research Resources Centre (CRAI) in 1996. It has since grown to become one of the world's leading archival libraries on subjects such as the Second Spanish Republic, the Spanish Civil War, exile, Francoist Spain and Spain's transition to democracy. In addition, the library has important materials on the Soviet Bloc and on the international political history of the twentieth history, particularly World War II. Context In 1937, during the Spanish Civil War, the government of the Spanish Republic participated in the Exposition Internationale des Arts et Techniques dans la vie moderne, better known as the Paris International Exhibition of 1937. The outbreak of the war in 1936 had a clear impact on the Spanish exhibition, and drew significant international attention to it. The Spanish pavilion included Pablo Picasso's Guernica, the now-famous depiction of the horrors of war, as well as Alexander Calder's sculpture Mercury Fountain and Joan Miró's painting Catalan peasant in revolt. The exhibition lasted from 25 May until 25 November 1937. The Pavilion was opened but not until July 12, and was located at Avenida del Trocadero near the pavilions of Germany and the Soviet Union. The project architect was the philosopher Jose Gaos, curator of the flag, the painter Josep Renau and writer Max Aub who organized the contents of the exhibition pavilion and commissioned the construction of the building to Josep Maria Sert and Luis Lacasa. Audiovisual production was by Luis Buñuel, appointed coordinator of the Propaganda the Information Service at the Embassy in Paris. The building The building of the Pavilion of the Republic, was conceived by its architect Josep Lluis Sert and Luis Lacasa as an empty container, almost three floors and walls. He left the floor open courtyard that communicated with, covered with a tarp, was the role of audience. On the first floor, devoted to propaganda and information on the situation of the country at war, it was accessed by a stairway and the second aimed at the arts and popular sections, where the large mural by Joan Miró , the Catalan peasant (now disappeared), it was accessed by a ramp, although there was a vertical access to the interior of the structure. It was built with a limitation of time and materials, many prefabricated panels and plywood, or synthetic, and adapting the plan to build