This article reflects on the place of history in international law and its critique. The turn to history in critical international law scholarship has attracted two broad objections. The first alleges a normative deficit: critical histories of international law are considered to be purely deconstructive, failing to direct or effect the construction of positive alternatives. The second objection is often less clearly articulated, with allegations that the turn to history is inappropriate or inadequate attached to arguments favouring the deployment of ‘juridical thinking’ for the purposes of international law’s critique. What is notable about these objections is the extent to which they have been advanced, elaborated upon or otherwise conceded by scholars turning to history to describe, explain and critique international law. Significantly, this appears to follow from either a tacit acceptance or strategic embrace of the very claims and forms of reasoning that critical history is uniquely positioned to challenge—namely, the particular ways in which international law relates past and present. This article traces the dangers and disadvantages of this move. It argues that a reflexive engagement with the forms and uses of history both within international legal reasoning and where international law is taken as the object of historical investigation might strengthen critical history at the point at which it currently falters. The article sets out the advantages in this regard of genealogy as history, critique, and therapy.