It was founded in the late 1990s by the Venezuelan journalist Carlos Henríquez Consalvi as a museum dedicated to collecting and preserving memories of the Salvadoran civil war, incorporating memories across the political spectrum.

The general enthusiasm of the public quickly prompted the MUPI to expand and it now includes a variety of exhibits that deal with various moments in the nation's past.

One of its projects has been the production of the documentary Cicatriz de la Memoria (Scars of Memory)[1] with U.S. historian Jeffrey Gould[2] regarding the 1932 Salvadoran peasant uprising.

Integral to the project was the idea of the "cine-forum," in which the MUPI took the documentary "on tour" throughout the country and abroad, organizing screenings in community centers, schools, and universities, followed by lively discussion sessions.

More recently, the MUPI has worked in an exhibit regarding the memory of the massacre of El Mozote, and has also worked in collaboration with the art museum MARTE in a joint exhibit about the acclaimed Salvadoran writer and artist, Salarrué.