Simon Ward was a predominantly unknown actor when he was cast as the central character of Sir Winston Churchill in this movie. Richard Attenborough threatened to quit the film if Carl Foreman (who didn't want Ward) didn't agree to his casting.
Writer and producer Carl Foreman was so impressed with Richard Attenborough's directorial debut, Oh! What a Lovely War (1969), that he offered him the opportunity to direct the film and play Lord Randolph Churchill. He declined the latter offer and then cast Robert Shaw.
Simon Ward was second choice for Sir Winston Churchill after Malcolm McDowell repeatedly declined the role.
This movie was released forty-two years after its source book "My Early Life: A Roving Commission", a.k.a. "My Early Life" and "A Roving Commission: My Early Life" by The Right Honourable Winston Churchill K.G.O.M.C.H.M.P. had been published.
Test audiences in the US reacted negatively, or with indifference, to scenes which had gone over well in the UK. Writer-producer Carl Foreman reported his surprise that so few Americans knew anything about David Lloyd George (making no reaction to the film's brief suggestions of Lloyd George's legendary reputation as a womanizer); and the last scene of the film, in which the elderly Churchill is confronted by the ghost of his father, occasioned so little reaction that Foreman elected to cut it entirely from American prints of the film. (This truncated version of the film is the one which now usually plays on British TV).