Denis Sefton Delmer (24 May 1904, Berlin, Germany – 4 September 1979, Lamarsh, Essex) was a Jewish-British journalist of Australian heritage and propagandist for the British government during the Second World War. Fluent in German, he became friendly with Ernst Röhm who arranged for him to interview Adolf Hitler in 1931. During hostilities he led a black propaganda campaign against Hitler by radio from England, so successfully that he was named in the Nazis' Black Book for immediate arrest after their planned invasion of Britain.