For much of the past millennium, the world's Jewish population has been concentrated in the Christian areas of the globe. As a result, Christian attitudes and behaviors toward Jews have been paramount in conditioning Jewish fate. Jews have had to contend regularly with a Christian environment--its dangers, its pressures, and its stimulation. Christian impact on the Jewish minority was particularly strong during the Middle Ages, when the powerful Roman Catholic Church exercised considerable control over key aspects of societal existence and when Christian imagery pervaded every facet of individual life. With the movement from the Middle Ages to modernity and the waning of the power of the Roman Catholic Church, widely held Christian attitudes and perceptions have maintained their hold on majority thinking and have continued to affect the Jewish minority.
Christians, over the ages, have been far less exposed to the influence of Jews. The major instance of Jewish power exercised over Christians was brief, but because it occurred during the formative period in Christian history, impressions of negative Jewish impact upon Christianity have been embedded in Christian consciousness. Also, during the Middle Ages, Jews constituted the only non-Christian element in many areas of western Christendom, thus presenting useful--although hardly appreciated--stimulation to the Christian majority.