Günther Quandt (28 July 1881 – 30 December 1954) was a German industrialist who founded an industrial empire that today includes BMW and Altana, a car and chemical company, respectively.

Werner married Eleanor Quandt, who after World War II helped to protect her brother-in-law, Günther, from prosecution by the Allies.

During World War I, under the leadership of Günther Quandt, his family supplied uniforms to the German army, which helped them accumulate a large fortune.

After the war, Günther used this fortune to acquire Accumulatorenfabrik AG (AFA), a battery manufacturer based in Hagen.

Quandt's businesses supplied ammunition, rifles, artillery and batteries, using slave labourers from concentration camps in at least three factories.

They found that Quandt was an important director in German industry, with several interlocking companies, syndicates and corporations.

To the surprise of many, he was judged to be a Mitläufer (fellow traveller), namely someone who accepted the National Socialist ideology but did not take an active part in crimes.

His two surviving sons, Herbert and Harald, administered their inheritance together, though Harald Quandt concentrated on the industrial plants Karlsruhe Augsburg AG (IWKA) which were involved in mechanical engineering and arms manufacture, while Herbert Quandt managed the investments in AFA/VARTA, Daimler-Benz and BMW.

His second marriage on 4 January 1921 in Bad Godesberg to Magda Ritschel produced another son, Harald Quandt.