“Knowing the Enemy: Nazi Foreign Intelligence in War, Holocaust and Postwar,” reveals the importance of ideologically-driven foreign intelligence reporting in the wartime radicalization of the Nazi dictatorship, and the continued prominence of Nazi discourses in postwar reports from German intelligence officers working with the U.S. Army and West German Federal Intelligence Service after 1945. For this project, I conducted extensive archival research in Germany and the United States, particularly in overlooked and files pertaining to the wartime activities of the Reichssicherheitshauptamt, Abwehr, Fremde Heere Ost, Auswärtiges Amt, and German General Staff, and the recently declassified intelligence files pertaining to the postwar activities of the Gehlen Organization, Bundesnachrichtendienst, and Foreign Military Studies Program. Applying the technique of close textual analysis to the underutilized intelligence reports themselves, I discovered that wartime German intelligence officials in military, civil service, and Party institutions all lent the appearance of professional objectivity to the racist and conspiratorial foreign policy beliefs held in the highest echelons of the Nazi dictatorship. The German foreign intelligence services’ often erroneous reporting on Great Britain, the Soviet Union, the United States, and international Jewry simultaneously figured in the radicalization of the regime’s military and anti-Jewish policies and served to confirm the ideological preconceptions of Hitler and his most loyal followers. After 1945, many of these same figures found employment with the Cold War West, using their “expertise” in Soviet affairs to advise the West German Government, U.S. Military, and CIA on Russian military and political matters. I chart considerable continuities in personnel and ideas from the wartime intelligence organizations into postwar West German and American intelligence institutions, as later reporting on the Soviet Union continued to reproduce the flawed wartime tropes of innate Russian military and racial inferiority.