In 1975, Jean Delumeau was appointed Professor at the Collège de France, where he held the chair Histoire des mentalités religieuses dans l'Occident moderne for twenty years. In loyalty to Lucien Febvre and Robert Mandrou, the historian chose not to mention " religions " but " mentalités religieuses ", and justified the chair title as the continuation of a now solid tradition : " Since the work of Marc Bloch and Philippe Ariès, Georges Duby and Robert Mandrou, the history of mentalities has acquired, in France in particular, its letters of nobility. "

During his years as a lecturer at the Collège de France, he successively explored fears, the need for security in our civilization, and dreams of happiness. The overall project aims to rediscover the many forms of fear in the West of yesteryear, such as structural fears, ageless fears situated at the deepest level, such as fear of the sea, antithetical fears of the other, fear of today and tomorrow, fear of the past; or the conjunctural fears that so often accompanied plagues in the past and paved the way for seditious movements.