>>507591751 (OP)>Did this really happen?Yes, read "Passovers of Blood" by Ariel Toaff.
>If it did, where's the evidence?Identical reports of blood libel across Europe in territories separated by language and religion. If peasants were simply inventing rumors about the Jews, why were their accusations always the same?
>And why did they go mad when he painted this?Because Jews worship their own tribe, and anything that makes them look bad (meaning anything accurate) makes them rage at their own repulsive reflection.