Argentina's National Museum of History and the National Museum of Fine Arts were created almost at the same time in Buenos Aires, towards the end of the nineteenth century. Many of the artefacts collected in both museums are of the same kind: oil paintings, drawings, engravings, and sculptures, depicting battles, portraits, landscapes, and costumbrista scenes. However, the artefacts in each institution were understood differently: those in the Museum of Fine Arts were considered as 'art', while those in the other museum were seen as historical documents. This differentiation between the material of art history and that of history deserves critical examination. The creation of each museum may explain this distinction, as well as offering a point of departure for further reflections about the way in which those artefacts have been exhibited, studied, and preserved. keywords museums, art, history, visual artefacts, Buenos Aires Oil paintings and watercolours, drawings, prints, sculptures in bronze, stone, or plaster; in the main, portraits, but also battle scenes, rural and urban landscapes, traditional scenes, and representations of historic and nation-founding events constitute the collections at both the Argentine National History Museum (MHN) and National Fine Arts Museum (MNBA). This is a characteristic held in common with history and art museums of the so-called 'western world' (i.e. with European cultural roots). However, scholarly studies of these two types of museums have generally followed separate paths and they have rarely been considered to be related. What are (or were) the criteria by which some paintings and sculptures have been considered, preserved, and exhibited as works of art and others as historical evidence? At first, attempting to answer this question seems to be too ambitious. Each institution has a story linked to the vicissitudes of its unique foundation and history. However, I would like to take this as a departure point for the following