Still only 23 when World War II broke out , he volunteered for the Royal Air Force and served as assistant conductor of the Royal Air Force Band and associate conductor of the Royal Air Force Symphony Orchestra . He also worked with the Crown Film Unit , which was producing documentary films to bolster the war effort . He took the RAF Symphony Orchestra to the Potsdam Conference for six concerts ; the leaders Winston Churchill , Harry S. Truman and Joseph Stalin were given the opportunity to make their requests , and Hollingsworth was surprised when Stalin chose Borodin 's 1st Symphony instead of a contemporary Soviet work
Potsdam Conference
Potsdam Conference
John Hollingsworth