Examples of what would be later called court Jews emerged during the Renaissance when local rulers used services of Jewish bankers for short-term loans. They lent money to nobles and in the process gained social influence.
Noble patrons of court Jews employed them as financiers, suppliers, diplomats and trade delegates. Court Jews could use their family connections, and connections between each other, to provision their sponsors with, among others things, food, arms, ammunition and precious metals.
In return for their services, court Jews gained social privileges - sometimes even titles - and could live outside the Jewish ghettoes. Some nobles wanted to keep their bankers in their own courts. And because they were under noble protection, they were exempted from rabbinical jurisdiction.
Some court Jews, unlike the majority of the other Jews, amassed large personal fortunes and gained political and social influence. Sometimes they were also prominent people in the local Jewish community and could use their influence to protect and influence their brethren. Sometimes they were the only Jews who could interact with the local high society and present petitions of the Jews to the ruler.
However, the court Jew had social connections and influence in the Christian world mainly through his noble patron. Due to the precarious social position of Jews, some nobles could just ignore their debts. If the sponsoring noble died, his Jewish financier could face exile or execution. Many debts were also canceled during pogroms when the Jewish creditor could disappear.
The court Jews, as the agents of the rulers, and in times of war as the purveyors and the treasurers of the state, enjoyed special privileges. They were under the jurisdiction of the court marshal, and were not compelled to wear the Jews' badge. They were permitted to stay wherever the emperor held his court, and to live anywhere in the German empire, even in places where no other Jews were allowed. Wherever they settled they could buy houses, slaughter meat according to the Jewish ritual, and maintain a rabbi. They could sell their goods wholesale and retail, and could not be taxed or assessed higher than the Christians.
Like all businessmen, Court Jews functioned at the mercy of the prevailing economy and changes in the regional/global economic conditions over which they had little or no control. Nevertheless, they were usually be assigned blame. Particularly odious, were their functions as shop keeping tradesmen and petty-lenders to the Christian working and agricultural classes on the continent. Their Sovereigns also sometimes assigned them the role of local tax collection from the above named classes of the ruler’s subjects. These roles built up a long (and some would say still) standing enmity between the Jewish (educated middle and upper) professional class; and the Christian lower middle, working, lower and agricultural classes. The resentments had far-reaching consequences in the history of European Jews.
These Christian classes were encouraged by their rulers and their church to blame Court Jews for the economic hardships that would periodically befall the local economy. The high taxes demanded by the ruler to pay off his war debts after the all too frequent wars, were blamed upon the Court Jews who had helped financed the war in the first place. Even though they had no choice in the matter. Moreover, they had no responsibility whatsoever for starting or fighting the war in the first place.
When the ruler’s bad economic decisions or profligate personal household spending resulted in a decline in national income or a rise in interest rates, with the resultant failure in small share Christian businesses and farms, the Court Jews domestically and abroad were easy to be blamed by the sovereign and his lesser nobles. It was an easy step to allow the people to periodically vent their anger against the great majority of Jews who were poor shopkeepers and tenant farmers (just like the Christians) as being responsible for economic hardships.
From 19th century central and eastern European industrialization and into the European wars and economic depressions of the 20th century the working classes and lower middle classes, small share entrepreneurs, and small scale farmers would draw upon these historical stereotypes. These Christian classes would rally against “International Jewish Money-Capitalism” and because of these beliefs support anti-Jewish policies. The most lasting and negative impact of this falsely alleged indirect economic rule, was the ingraining in the popular view of their being a “hidden” hand of Jewish influence in domestic economic events caused by an even more “hidden” hand of international Jewish economic power.
Important as court Jews were also Samuel Oppenheimer, who went from Heidelberg to Vienna, and Samson Wertheimer (Wertheimher) from Worms. Oppenheimer, who was appointed chief court factor, together with his two sons Emanuel and Wolf, and Wertheimer, who was at first associated with him, devoted their time and talents to the service of Austria and the House of Habsburg: during the Rhenish, French, Turkish, and Spanish wars they loaned millions of florins for provisions, munitions, etc. Wertheimer, who, by title at least, was also chief court factor to the electors of Mayence, the Palatinate, and Treves, received from the emperor a chain of honor with his miniature.
Samson Wertheimer was succeeded as court factor by his son Wolf. Contemporaneous with him was Leffmann Behrends, or Liepmann Cohen, of Hanover, court factor and agent of the elector Ernest Augustus and of the duke Rudolf August of Brunswick. He also had relationships with several other rulers and high dignitaries. Behrends' two sons, Mordecai Gumpel and Isaac, received the same titles as he, chief court factors and agents. Isaac Cohen's father-in-law, Behrend Lehman, called also Bärmann Halberstadt, was a court factor of Saxony, with the title of "Resident"; and his son Lehman Behrend was called to Dresden as court factor by King Augustus the Strong. Moses Bonaventura of Prague was also court Jew of Saxony in 1679.
There were court Jews at all the petty German courts; e.g., Zacharias Seligmann (1694) in the service of the Prince of Hesse-Homburg, and others in the service of the dukes of Mecklenburg. Others mentioned toward the end of the seventeenth century are: Bendix and Ruben Goldschmidt of Homburg; Michael Hinrichsen of Glückstadt, who soon associated himself with Moses Israel Fürst, and whose son, Reuben Hinrichsen, in 1750 had a fixed salary as court agent. About this time the court agent Wolf lived at the court of Frederick III of Mecklenburg-Strelitz. Disputes with the court Jews often led to protracted lawsuits.
The last actual court Jews were Israel Jacobson, court agent of Brunswick, and Wolf Breidenbach, factor to the Elector of Hesse, both of whom occupy honorable positions in the history of the Jews.







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In fiction, Isaac the Jew in Sir Walter Scott's "Ivanhoe" serves this puropse to Prince John and other nobles.