In the works of Freud, the concept of childhood psychic trauma evolves in the direction of increasing complexity. The authors maintain that this expansion corresponds to a new conception of retroactive temporality (Nachträglich), which is precisely the one we use in the analytic process of reconstruction and historicization from the present toward the past. We are thus led to differentiate the extreme form of the unassimilable 'pure' Trauma, nearly pure death drive, from the retroactively historicized forms which are reintegrated into the continuity of a vital flow of time that we 'invent' in analytic work.