Anti-Semitism, sometimes called history’s oldest hatred, is hostility or prejudice against Jewish people. The Nazi Holocaust is history’s most extreme example of anti-Semitism. Anti-Semitism did not begin with Adolf Hitler: Anti-Semitic attitudes date back to ancient times. In much of Europe throughout the Middle Ages, Jewish people were denied citizenship and forced to live in ghettos. Anti-Jewish riots called pogroms swept the Russian Empire during the nineteenth and early twentieth centuries, and anti-Semitic incidents have increased in parts of Europe, the Middle East and North America in the last several years.