Takkanot Shum

The Takkanot Shum (Hebrew: תקנות שו"ם‎‎), or Enactments of SHU"M were a set of decrees formulated and agreed upon over a period of decades by the leaders of three of the central cities of Medieval Rhineland Jewry: Speyer, Worms, and Mainz. The initials of the Hebrew names for these cities, Shpira, Vermayza, and Magentza form the initials SHUM. While these regulations were intended to address the problems of that time, they had an effect on European Jewry that lasted centuries.

Following the devastation of much of the Jewish communities of the Rhineland during the First Crusade, Jews who had formerly made their livings as itinerant merchants could no longer travel safely, and had to find careers in the cities which they lived. Many became local merchants; others became moneylenders. This drastically increased the rate of commerce between Jews and non-Jews, and, thus, litigation both internally amongst Jews and between Jews and Non-Jews. Simultaneously, heavy taxes were being levied on the Jewish communities by the local government, taxes which many Jews at the time felt were being unfairly distributed by the leaders of the local kehilla. The increasing internal and external pressures on the Jewish community, together with their recent near destruction during the Crusades, caused the leaders of the time to take the step of instituting broad decrees to strengthen their communities.

In or around 1160, a synod was held in Troyes. This synod was led by Rabbeinu Tam, his brother, the Rashbam, both grandchildren of Rashi, and Eliezer ben Nathan (the Ra'avan). Over 250 rabbis from communities all over France attended as well. A number of communal decrees were enacted at the synod covering both Jewish-Gentile relations as well as matters relating internally to the Jewish community. Examples of such decrees include:

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