Frankfurt is one of the oldest and most important settlements of Jews in Germany. As in other European cities and regions, the Jews were subject in the Middle Ages and modern times to recurrent bloody pogroms and expulsions, mostly as a result of religious fanaticism for example in 1241 and 1349 and in the Fettmilch uprising 1614. Nevertheless, Jews have lived here almost continuously from the Middle Ages to the present day. Their status was determined by the socalled residence codes (Stättigkeitsordnungen), which placed them under explicit imperial protection from 1616 onwards. From this date they were spared from expulsions in Frankfurt. Starting in the early 16th century the number of Jews in Frankfurt rose from a few hundred to over 3,000 in the 18th century. This growth in population was due partly to natural increase but was mainly the result of immigration from other cities and regions. There were periodic waves of immigration when Jews were expelled from other areas and sought refuge in the relative safety of Frankfurt. In 1498 for example many Jews came from Nuremberg after being expelled from the town. As a trading centre with its own fair, Frankfurt also had commercial attractions, and finally the governing classes (city council and emperor) had a certain interest in attracting Jews as a tax base. At the same time, the city council, influenced by antisemitic feeling among the Christian citizens, tried to prevent an over rapid increase in the number of Jews in the city, limiting Jewish immigrants to those who had at least 1,000 guilders. In addition, the maximum number of Jewish households was set at 500 and Jewish weddings were limited to 12 a year.