The Nazis did not invent anti-semitism. They just used it to gain and maintain power. Anti-semitism is thousands of years old, and most likely stems from the refusal of Jewish people to change their way of life and religion and because once they were dispersed from their own country, Israel, they were "foreigners," no matter what countries they lived in. Spain, in the 14th century, killed Jewish people who refused to convert to Catholicism. England, during certain periods of its history, did not permit Jews to live there. Other European countries had policies whereby Jewish people could not vote, own property, etc. Most "isms" stem from a people's "otherness," and since Jewish people were different, anti-semitism was a consequence early in their history.