Through a combination of heavy one-off taxes and loans extorted with menaces, many secular rulers had found the Jews to be a valuable source of revenue. The rise of Italian banking in the late thirteenth century had diminished the importance of Jews to royal finance, just as poisonously anti-Semitic attitudes arose across Europe, making mistreatment of Jewish communities a tool of easy populist policy. Jews were lampooned in public plays, attacked by mobs, and became the subjects of absurd myths which portrayed them as child-murderers and sexual monsters.
