I would guess that if you asked Jews what the worst book of the 20th century was, Mein Kampf (My Struggle) would be chosen by many or most Jews. The book was written by Adolf Hitler and published in two volumes in 1925 and 1926 while he was incarcerated as a result of his attempt to take over the German government by force in 1923. It contains many anti-Semitic themes and foreshadowed what he would do to European Jewry if he gained power.