As it became clear that the Battle of Stalingrad was not going to be a victory for the Reich, Hitler issued the production of localised nerve gas in order to prevent the Soviets from pushing the invasion back. Used extensively and unfavourably in World War I, the Führer looked down upon it until he felt he had no choice but use this weapon of mass destruction. So, in December 1942, full producing started, under the watchful eye of the SS.