Global legal pluralism in France was an approach strongly tied to the institutionalization of the field of ethnology, colonial law, and colonial administration in the interwar period. As France’s overseas possessions greatly expanded, and many colonial subjects were still administered according to a plurality of legal rules, with customary rules and French administrative or criminal law, ethnologists and colonial administrators were interested in raising the question of whether such combination of legal sources hampered or accelerated the “integration” of colonial subjects to the French Republic. Not surprisingly then, the strong attachment of a global legal pluralistic approach to the administration of colonial subjects in the field of anthropology has thus been profoundly questioned after the age of decolonization. By tracing the theoretical and normative ideas that inspired prominent ethnologists associated with the global legal pluralist approach in the colonial age, this chapter thus adds a building block to our comprehension of the evolution of the French colonial field and its impact on ethnology and global legal pluralism, before, during, and after the age of colonization.