Kung Fu Capers - Movie Music Tribute

When Bill and his band of Merry "Eckie-Thumpians" are marching to take over government (particularly when it is in "sepia" tone) there's a piece of music being played. I have a fairly strong suspicion this is a piece of a movie score, and cannot remember what the movie is. Have a feeling it's about a revolution of some sort. (One of Eisenstein's classics????)

Thanks for any help.