This chapter discusses two different historical junctions where the Enlightenment and Jewish history collide and converge. The first junction is the late Enlightenment’s debates over what defines the Enlightenment, which formed modern discourses of Jewish reformation and reconstruction. The second junction is the massive Jewish immigration wave to America between 1880 and WWI, which produced a vivid and optimistic proliferation of social thought pertaining to the Jews as ideal citizens of the modern world of mobility and the modern city. These two junctions mark two boundaries where Jewishness collides or converges with the Enlightenment—respectively, as the negative exemplarity, the other within, or the positive exemplarity, the avant-garde. In conclusion, it is contended that modern Jewish history is still tied to universalized struggles over the values of both local and global civil spheres.