The article discusses the evolution from the 1966–1967 “first” Russell Tribunal, an unofficial and political gathering that censured the USA for its aggression in Vietnam, to the “second” Russell Tribunal, which took place in Rome and Brussels between 1974 and 1976 and put human rights violations in Latin America in the international spotlight. Both Tribunals shared a profound anti-Americanism and an explicit proximity to Third Worldism. Yet, there was also an important difference, since the language of human rights shaped only the “second” Tribunal. The article is mostly based on documentary sources held by the Fondazione Lelio and Lisli Basso in Rome. This choice is based on the importance Italian Senator Lelio Basso had for the Tribunal. Basso was the main organizer and the driving force of the Tribunal and coordinated many transnational groups in support of this event. Moreover, his intellectual reflections on decolonization as a revolutionary force and his fierce anti-Americanism offered a blueprint for the proceedings and the sentence of the Tribunal. Bringing together the recent literature on the emergence of human rights during the 1970s and that on European anti-Americanism, the article shows how some prominent European intellectuals and politicians appropriated human rights jargon to criticize American foreign policy and denounce its responsibilities for ongoing human rights violations in Latin America. In doing so, it argues that the human rights language renewed European anti-Americanism during the 1970s.