- David Morrissey
- Narrator
- Winston Churchill
- Self
- Adolf Hitler
- Self
- Franklin D. Roosevelt
- Self
- Joseph Stalin
- Self
- John Baddeley
- Winston Churchill / Robert Jackson (voice)
- Wolf Kahler
- Adolf Hitler
- Peter Marinker
- Franklin D. Roosevelt
- Diran Meghreblian
- Iosif Stalin
- Fernando Tiberini
- Joseph Goebbels
- Max Bollinger
- Nikita Kruschev / Georgi Dimitrov (voice)
- Giancarlo Cicconi
- Count Ciano
- Walter Bohnacker
- General Halder
- Werner Kastor
- Major Engel
- Steven Pacey
- Jock Cloville
- William Roberts
- Harry Hopkins / Henry Morgenthau Jr. / Harold L. Ickes / Doctor Charles M. Wilson / General Dwight E. Eisenhower (voice)
- Ed Bishop
- Henry L. Stimson
- Kate Harper
- Eleanor Roosevelt / Marguerite LeHand / Frances Perkins (voice)
- Douglas Blackwell
- Lord Halifax
- Alan Marriott
- Elliott Roosevelt
- Michael Lumsden
- Anthony Eden
- Trevor Nichols
- General Alan Brooke
- Anna Barry
- Clementine Churchill
- Neil McCaul
- General Mark W. Clark
- Eva Braun
- Self
- Joseph Goebbels
- Self
- Constantine Gregory
- (voice)
- Harry Hopkins
- Self
- Benito Mussolini
- Self
