Wilhelm Keppler was a German industrialist who became State Secretary for Special Assignments of the Reich Foreign Office (1939-1945). He held the Golden Party Badge and was a member of the Reichstag. Keppler was a founder and member of what was first the "Friends of the German Economy", which channeled funds to the Party, and became the "Circle of Friends" of Heinrich Himmler. He held the rank of SS-Obergruppenfuehrer, habing joined the Schutzstaffel in 1936.
Keppler had been war materials expert and economic adviser to Adolf Hitler (1932-1938), with specific roles including Special Commisioner for German war materials (1934), and general expert for German raw materials in the Four Year Plan (1936), advising Hermann Goering. He also held board positions in businesses owned by or connected with the Reich, including the Kontinental OEL A.G. (oil company) and Deutsche Unsiedlungs-Treuhandgesellschaft (financial services).
In 1934, he met, along with Hitler and Ribbentrop, with officials of the General Motors Overseas Corporation. General Motors had owned Opel since 1929. On May 3, 1934, an excited Hitler told Keppler, "I have been thinking all night about the many things that these Opel men told me." He instructed Keppler, "Get in touch with them before they leave Berlin." 
He was intimately involved in the Anschluss, as special German Representative for Austrian affairs, and then Reich Commissioner for Austria, both in 1938. Turning his attention to Slovakia, he was Reich Commissioner there in 1939.
As a defendant in the Ministries Case of the Nuremberg Military Tribunals, he received a ten year sentence for aggressive war, invasion and spoilation of other countries, atrocities against civilians and membership in a criminal organization, the SS.
- Edwin Black (23 April 2007), Hitler's Carmaker: The Inside Story of How General Motors Helped Mobilize the Third Reich (Part 1), History News Network, George Mason University