This study aims to highlight the genesis of the discursive marker in any event by an examination of its occurrences in the Frantext corpus. It draws in particular on the work of Combettes. (1995), and continues them over a longer period of time and through an approach quantitative, including the various variants of the marker. The examination shows that it is in the interwar that this is the case. the functioning of the prepositional word combination became apparent after a series of changes that can be seen as a process of constructionalisation (Traugott de Trousdale, 2013).