During the 1970s in Brazil a social space directed towards health problems on the population level, called collective health, was created and institutionalised. To what extent did this Brazilian invention correspond to a specific socio‐historical practice? The works published on this topic have considered social medicine as a homogeneous phenomenon without empirically studying the specificities of national experiences. To bridge this gap, a historical study on the genesis of collective health in Brazil was carried out based on Bourdieu's field theory. The interaction between the paths of the founders and the conditions of historical possibilities were researched through documentary and bibliographical sources, as well as through in‐depth interviews of the founders. This social space originated from a meeting of agents with different social backgrounds but who interconnected, creating a structure that was independent of each agent considered individually. One of the components of this establishment was the joining of theoretical production and the implementation of health reforms that resulted in the organisation of a universal health system. This study attempts to show how the international political situation and the contradictions of the national crisis created a universe of possibilities, allowing for the genesis of this sui generis space in Brazil.