The Rhineland under the French (1794 - 1813)
"In 1815 the time of French influence was over, but had left behind far-reaching changes, which had been appreciated as a change for the better, especially in the areas of commercial law and administration. Therefore the population also resisted having to sacrifice such achievements for the sake of Prussian citizenship. Consequently, the Code Civil, also known as the Code Napoleon, remained in force as the first citizens' compendium of laws left of the Rhine until it was superseded by the "Bürgerliches Gesetzbuch" (modern German civil code). Prussia itself had been forced to adopt the superior French State as a model and to carry out reforms. These reforms paved the way
for the constitutional state of the 19th century."