This chapter aims to demonstrate how Maurice Halbwachs’s work between the two world wars can be seen as an extension of the pro-gram Émile Durkheim began to sketch out in his conclusion to Ele-mentary Forms. More than Marcel Mauss—who strangely only rarely quotes and uses Elementary Forms in his texts after 1918 (Marcel 2012, 2019)—Halbwachs can be considered to be the successor of Durkheim’s sociology of knowledge program, all the more so as Mauss, in some ways, did not really want to assume Durkheim’s leg-acy (Marcel 2001).Halbwachs can be seen as the true continuation of Durkheim, espe-cially if we keep in mind how both Durkheim’s as well as Halbwachs’s sociology of religion are embedded within a theory of collective repre-sentations and classifi cations. Symptomatically, it is Halbwachs who, in 1918, satisfi es Lucien Lévy-Bruhl’s request to write an article about “Durkheim’s Doctrine” for the Revue philosophique (Halbwachs 1918) and who, in 1925, writes a book titled The Origins of Religious Senti-ment according to Durkheim (Halbwachs 1925a). In a letter to Mauss in 1924 he also states that he considers the book he is working on, The Social Frameworks of Memory (Halbwachs 1925b), to be “bound to Durkheim’s and Mauss’s theory of intelligence and categories” (Hirsch 2012: 226). At that time, memory was already a privileged object of investigation for him1 and constituted his main contribution to the so-ciology of mental functions, as previously clarifi ed by Durkheim and Mauss in their text about classifi cations (Durkheim and Mauss 1903)