Abstract: Modern comparative lawyers tend to date the foundation of their discipline to the nineteenth century and to the promulgation of the great European codes. This article claims that one could make an argument that comparative law is to be found in the ancient world, with some suggestion of it in the early writings of Aristotle’s Politics; that despite the multiplicity of legal sources it is not often found in the early or high middle ages; that there are hints of it in the commentators of the later middle ages; that in a very real sense it can be found in the ideas of the French legal thinkers of the sixteenth century; and that one can trace a relatively clean line of sources from the sixteenth century to whatever nineteenth-century authors one chooses to focus on as the founders of the discipline that produced the First International Congress of Comparative Law in 1900.