The first catalogue, published in 1906, already reflected the multi-faceted nature of the collection, which included paintings, sculpture, drawings, prints, weaponry, medals, coins, pottery, musical instruments, pre-Columbian objects, and religious silverwork.
The collection was divided into three sections – Fine Arts, History and Archaeology – following the advice of José Villegas, the senior curator for the Prado Museum at the time.
The general interest in preserving local rural heritage, which was rapidly disappearing as a direct result of the industrial revolution, led to the creation of the Ethnographic Commission in 1914. Donations and acquisitions organised by the commission gave shape to the fourth and essential part of the museum’s collection. This section was responsible for gathering information on the various aspects of traditional daily life in the Basque Country. The department’s prestige grew from year to year, eventually becoming a reference for other ethnographic museums opening up in Spain.