The criticisms that Kant levels at acts of conquest and forced annexation are multiple and varied. At the same time however, he recognises that the vast majority of existing states are de facto the product of a history made up of conquests and forced annexations, and does not appear to believe that this fact calls into question their legitimacy. How can this view be reconciled with his condemnation of forced annexation and conquest? Exactly what does the wrong committed by acts of conquest or forced annexation consist of? Should this wrong not always call for rectification? This paper will address these questions by focusing on the temporal dimension of territorial rights, and more specifically, by examining whether, and if so to what extent, the validity of territorial claims can be affected by the passage of time and by changing circumstances.