Coutume
Coutumes were the customary laws of France.
Developed under feudalism during the Middle Ages and in the early modern period, the coutumes were the laws asserted and enforced by the French kings and their vassals, especially in the lands of the Île-de-France, to the exclusion of Roman law. The area where the French customary law (droit coutumier) was in force was known as the pays de coutume. In the south of France (pays de droit écrit) Roman law remained paramount. The line separating the two areas was generally the river Loire, from Geneva to the mouth of the Charente.