Jewish civil emancipation is normally discussed in the context of changes in attitudes toward Jews, commercial restructuring, and the Enlightenment atmosphere, all leading up to the French Revolution and the decision of 1791 to grant French Jews full citizenship. All of these factors were important. However, were it not for the legal revolution that occurred during this time, ending the reign of ius commune and customary law and replacing both with the Napoleonic Code Civil, emancipation would not have occurred, certainly not in the form it did. This was no instant rejection of the past, however, but the result of a lengthy process in which the incompatibility of the Jews’ status as cives in ius commune ran up against, and had to be squared with, the application of that law in a state that was confessional and whose legal system was hierarchical: different laws for different social strata. Ultimately, this incompatibility proved both unbridgeable and intolerable. The choice was either to remove the legal and confessional impediments, that is, to grant Jews full legal equality, or to remain politically mired in the past. The latter was the course of the Papal State. Yet, paradoxically, it is by studying the fortunes of this incompatibility in just this setting that the process, its snares, and the reasons for emancipation, as well as its eventual failure in some places, become clear.