There are a few scenes in really good movies that capture the zeitgeist of the moment...

[CBHagman]

9. Just a note on the filming of that scene in "Casablanca."

In The Making of Casablanca: Bogart, Bergman and World War II (also known as Round Up the Usual Suspects Aljean Harmetz provides some interesting background on the cast (e.g., the anti-Nazi actor Conrad Veidt, cast as the evil Major Strasser) and production, including the realities of filming during wartime -- with immigrant extras, strictly observed curfews, and so forth. From what I understand, some of the extras had also fled wartime Europe and were found to be in tears at the end of takes for the Marseillaise sequence.

http://books.google.com/books?id=YSJcTLPP9QcC&pg=PA257&lpg=PA257&dq=aljean+harmetz+marseillaise&source=bl&ots=NrHopQlr3U&sig=xW5ovH4Mu3PaTrpVw26Kp51xFB0&hl=en&sa=X&ei=5hv6TqblAeO-2AXTjYHPBw&ved=0CCoQ6AEwAA#v=onepage&q&f=false