The Nazi regime elevated anti-Semitism to a scientific discipline, “Jew research” (Judenforschung), which underpinned regime propaganda. At the intersection between the academic rationalization of Jew hatred and propagandistic agitation was the magazine Welt-Dienst (World-Service, Service Mondiale). It was published from the end of 1933 to the beginning of 1945, at the end in more than twenty languages, Welt-Dienst was founded privately to create a central organization of an “Internationale of Anti-Semites.” It was quickly incorporated by Alfred Rosenberg, who thereby acquired a means of anonymously disseminating anti-Semitic propaganda worldwide. The Welt-Dienst worked closely with the Institute for the Study of the Jewish Question, even sharing a space with it in Frankfurt am Main. Both profited from the Aryanization of Jewish libraries and the raids of the Reichsleiter Rosenberg Taskforce which plundered Jewish property for “Jew research” in wake of the Wehrmacht. The Welt-Dienst articles compiled based on the possessions of the murdered European Jews served the needs of the regime and helped bolster the war unleashed by the Third Reich against the Jews. While other Nazi propaganda institutions have recently received researchers’ attention, the Welt-Dienst has been neglected, its founder Ulrich Fleischhauer being considered an eccentric outsider. This article is supposed to outline and highlight the relevance and history of the Welt-Dienst and show that its role as a mediator between propaganda and science was more significant than previously assumed.