This chapter focuses exclusively on medieval Jewish civilization, from the fall of the Roman Empire to about 1492. It includes alphabetically organized entries, written by scholars from around the world, include biographies, countries, events, social history, and religious concepts. The most famous "genizah" is the Cairo Genizah. Today the contents of the Cairo Genizah are spread among libraries in Philadelphia, New York, Cambridge, Oxford, Manchester, London, Paris, Budapest, St. Petersburg, Jerusalem, and a few other cities. The Jews of Germany, as elsewhere, governed their internal communities and their own personal lives in accord with talmudic law and the enactment of specific ordinances. The Christian secular and ecclesiastical authorities settled the conditions of mutual relations by setting rules that constitute what is known as the "Jewry law", lex Iudeorum. The legal status of the Jews deteriorated significantly under the reign of Rudolf of Habsburg.