This thesis focuses on the evolution of the french-speaking sociology in Quebec, from the first monographs of Léon Gérin to the sociological enquiries in the aftermath of World War II by the School of Laval. It aims to underline the ideological background of the sociological science, to emphasize the political and social discourses that nourish its thoughts. Sociology is no more than a rationalization of the common culture, to use the expression of Fernand Dumont: it repudiates the common culture only after it has been enriched by it.That is the reason why this thesis refuses to consider the past of the sociological discipline as some sort of prehistory. It refuses to consider its development in the XXth century as a natural, teleological and monolithic process, as some historians have done throughout the 1960s and 1980s. Without forgetting the importance of the process of specialization and institutionalization of the discipline during the XXth century, the author has thought better to explore the ideas and ideologies of the social scientists, from 1886 to 1955.The author has classified, for that period, three different sociologies: the sociology of Le Play, the doctrinal sociology, and the personnalist sociology.Le Plays sociology (1886-1910) owes its strongest development to Léon Gérin, a civil servant who was the disciple of Tourville et Demolins. Gérin has made some monographs on rural villages and french-Canadian families, based on the empirical methods of the School of the Social Science.The doctrinal sociology (1910-1940) has one of its finest representative in Esdras Minville, professor at the HEC. It has two main characteristics. On one hand, it stays always very close to the science of social economy; on the other hand, it criticizes capitalism because it creates class struggles and the pauperization of the French-Canadian economy.The personnalist sociology (1940-1955) emerges with (between many others) Georges-Henri Lévesque and Jean-Charles Falardeau. In union with the constitution of the welfare-State and the techno-scientific complex, it becomes a piece of both the research centers of the universities and the bureaucratic apparatus of the State.This division between three different sociologies does not prevent an intellectual tradition. Beside some common themes (solidarity, culture, education), and besides a shared nationalism, the French-Canadian sociology before 1960, because it is rooted in Catholicism, determines a certain epistemology. That is what this thesis tries to prove.