Jewish law (halakhah) was the major integrative factor in Jewish life from early geonic times (eighth century) until the onset of the modern era. With Jewry's ever-increasing geographic dispersion and political incapacity, Jewish identity was shaped increasingly by Jewish law. It defined the broad sphere of religious observance and significantly influenced the norms and practice of communal governance, and its study was a central spiritual and intellectual experience. Jewish law was created in rabbinic academies and courts by individual scholars and by communal custom and enactment. Until the modern period, Jewish law responded to the major challenges in Jewish life, and the historical-geographic grid of legal creativity paralleled the development of the major centers of Jewish life.

Chronological Periods, Geographic Centers, and Authorities

The geonic period most likely begins with the Islamic conquest of Babylon in about 650; indeed it seems that the establishment of...