Jeremy Isaacs had been inspired to look at the production of a long form documentary series about the Second World War following the BBC's broadcast of its series "The Great War" in 1964. However, the BBC series, which had been produced in collaboration with the Imperial War Museum, featured a mix of contemporary film footage from the period, and film recreations, which caused a souring of relations between the BBC and the Imperial War Museum. As a consequence, Isaacs was determined to have his programme be as authentic as possible.