ABSTRACT
Liberal thought about the nature of international relations has a long tradition dating back to the eighteenth and nineteenth centuries. During these centuries liberal philosophers and political thinkers debated the difficulties of establishing just, orderly and peaceful relations between peoples. One of the most systematic and thoughtful accounts of the problems of world peace was produced by the German philosopher Immanuel Kant in 1795 in an essay entitled Perpetual Peace. Kantian thought has been profoundly influential in the development of liberalism in IR (see below).
