In early modern times the Christian majority in Europe often justified the political and economic restrictions placed on European Jews by invoking the necessity fro maintaining religious conformity. As the concept of religious toleration became more accepted, however a new argument for Jewish repression developed. After a French linguist, Joseph Ernest Renan (1823-1892) advanced the idea that the Aryans and the Semites were different races, a group of German writers drew on his theory to assert that Jews were members of a distinct an inferior race. By the 1870s this anti-Semitism had spread across Germany, Austria, Hungary, France and Russia, often resulting in the persecution of Jews. One of the worst outbreaks of anti Jewish violence took place in 1881 in Russia. A major consequence of these anti Jewish pogroms ( a Russian word meaning "devastation") was a mass exodus of Jews from Russia to other...