Liberationist Christianity in Argentina was a more heterogeneous phenomenon than is often assumed. Its internal differences had, by the mid-1970s, carved irreconcilable fractures in the most visible and influential group of the movement, the Third World Priests (MSTM). Placing the movement within the longer historical context of twentieth-century Argentine religious and political developments allows us to appreciate also the diversity of its origins. Liberationist Christianity represented a new movement and phenomenon in Argentina and the Christian sphere in the 1960s. However, a variety of important precursors fed into its mobilisation, and continuities existed with previous forms of Catholicism in Argentina: on the one hand, dominant integral Catholic and nationalist sectors dating back to the 1930s; and on the other, more liberal and pluralist sectors associated with the New Christendom project. Moreover, Peronism, the populist political movement that erupted onto the scene in the mid-1940s and was initially associated with Catholic nationalism, impacted the social and political orientations of many Christian tendencies. By the end of the 1950s, various elements of Argentine society, from Marxists and the wider left to Christians of many backgrounds, had to contend with Peronism's stubborn capacity for survival and hegemony among the primarily working-class population. This shared project of coming to terms with Peronism coalesced with simultaneous developments: the flourishing of humanist tendencies; the emergence of a new left inspired by the Cuban example and other national liberation projects; the Second Vatican Council and religious reflections on modernity; and intermittent outbreaks of rebellion and militant action in the labour and student movements.

This chapter attempts to navigate some of the complex web of interconnections and confrontations between Peronism, Christianity and the wider left, in the context of political changes between 1930 and the mid-1960s that fed into the liberationist Christian movement. It begins with a burgeoning integral Catholicism that became a considerable force in the 1930s in conjunction with a form of authoritarian nationalist politics. Subsequently, a brief assessment of the historical emergence of Peronism will outline its relation to Catholicism. In this context, we can see the appearance of new Catholic tendencies, rooted in pluralism and Maritainian theology and opposed to both Peronism and the more hardline anti-liberal integralism.