Sergei Eisenstein - Battleship Potemkin (1925)

Full film to view at google video.

"Deliberately written as a revolutionary propaganda film, Eisenstein used this film to test his theories of "montage". The revolutionary Soviet filmmakers of the Kuleshov school of filmmaking were experimenting with the effect of films on the audience, and Eisenstein edited the film in a way that would produce the greatest emotional response, so that the viewer would feel sympathy for the rebellious sailors of the battleship Potemkin and hatred for their cruel overlords. In the manner of most propaganda, the story was written in a very simplistic fashion, so that the audience could clearly see whom they could sympathize with."
http://en.wikipedia.org/wiki/The_Battleship_Potemkin