How did legal customs in northern France differ from those in southern France?

In the context of pre-revolutionary French legal history, France was divided into two distinct legal zones: the north and the south.12

• Northern France: Known as the land of customary law (pays de coutume), the legal system here was based largely on feudal Frankish and Germanic institutions. While these regional customs incorporated elements of Roman law, canon law, and Carolingian capitularies, Germanic elements predominated.21
• Southern France: Known as the pays de droit écrit ("land of written law"), this region was characterized by a higher concentration of Gallo-Romans compared to Franks. Consequently, the custom of each district was based primarily on the vulgar law of the Lex Romana Visigothorum.1

This legal diversity meant that a traveler in France could encounter different laws in almost every region. These local customs primarily governed matters of private law, such as property and succession. It was not until the enactment of the Napoleonic Code in 1804 that France achieved a unified civil law system, replacing the fragmented customary and Roman-based laws with a single, national body of legislation.234