On March 30, 1973, three weeks after Hctor Cmpora won the first presidential elections in which candidates on a Peronist ticket could run since 1955, rock producer Jorge lvarez, himself a sympathizer of left-wing Peronism, carried out a peculiar celebration. Convinced that Cmpora's triumph had been propelled by young people's zeal—as expressed in their increasing affiliation with the Juventud Peronista (Peronist Youth, or JP), an organization linked to the Montoneros—he convened a rock festival, at which the most prominent bands and singers of what journalists had begun to dub rock nacional went onstage. Among them were La Pesada del Rock- 'n'Roll, the duo Sui Gneris, and Luis Alberto Spinetta with Pescado Rabioso. In spite of the rain, 20,000 people attended the Festival of Liberation, mostly muchachos from every working- and middle-class corner of Buenos Aires, as one journalist depicted them, also noting that while the JP tried to raise chants from the audience, the boys acted as if they were untouched by the political overtones of the festival.