We have a poster of this in our kitchen and I was pondering the characters and casting and a thought occurred to me that maybe on some subconscious level this movie was about the world situation of the time with Rhett Butler representing American isolationism and the Leslie Howerd Ashley Wilkes character being England and her old world values. This might not stand up to much scrutiny though - I still stick with the notion that The Lord of the Rings is about the Great War. Having just done a search on Gone with the Wind I ask you to consider this - would someone from say Blitzed London watching Gable's cynical gun-running profiteer think 'typical American'? It's interesting to note that Margaret Mitchell favoured Basil Rathbone for the main lead.
While searching the web I came across this movie that from the write-up looks interesting -Les Uns et les autres - a Claude Lelouche movie based on the lives of a series of musicians Josephine Baker, Glenn Miller and so on caught up in World War Two. More here. I'll have to track it down. They ought to have had Wilson Keppel and Betty for an English sequence. Seems like it was retitled Bolero - that is why I havent seen it I expect.