During a speech at the Reichstag on 30 January 1939, German Führer Adolf Hitler threatened "the annihilation of the Jewish race in Europe" in the event of war:
If international finance Jewry inside and outside Europe should succeed in plunging the nations once more into a world war, the result will be not the Bolshevization of the earth and thereby the victory of Jewry, but the annihilation of the Jewish race in Europe.
These words were similar to comments that Hitler had previously made to foreign politicians in private meetings after the Kristallnacht pogrom in November 1938. The speech was made in the context of Nazi attempts to increase Jewish emigration from Germany, before the outbreak of World War II in September 1939.
Allusions to "Hitler's prophecy" by Nazi leaders and in Nazi propaganda were common after 30 January 1941, when Hitler mentioned it again in a speech. The prophecy took on new meaning with the invasion of the Soviet Union in June 1941 and the German declaration of war against the United States that December, both of which facilitated an acceleration of the systematic mass murder of Jews. In late 1941, Nazi propaganda chief Joseph Goebbels stated that the prophecy was being fulfilled while justifying the mass deportation of Jews from Germany. On 30 September 1942, Hitler referenced the prophecy in another speech, which was adapted into a November issue of Parole der Woche titled "They Will Stop Laughing!!!" Hitler continued to invoke the prophecy as the war went against Germany and referenced it in his last will and testament. Frequently used by Nazi leaders when alluding to their systematic murder of Jews, the prophecy became a leitmotif of the Final Solution and it is perhaps the best-known phrase from Hitler's speeches.
The historical significance of the prophecy is debated between the schools of functionalism and intentionalism: intentionalists view it as proof of Hitler's previously developed master plan to systematically murder the European Jews, while functionalists argue that "annihilation" was not meant or understood to mean mass murder, at least initially. The prophecy is cited by historians as an example of the Nazis' belief in an international Jewish conspiracy that supposedly started the war. Additionally, despite its vagueness—not explaining how the annihilation would come about—the prophecy is cited as evidence that Germans were aware that Jews were being exterminated.