Movies where the thematic elements revolve around a group of people banding together against an oppressive force, but not really a chosen one style story. I have Braveheart in mind but I don't know if that really hits the same notes, because so much of it is also a love revenge story.
:im-doing-my-part: Starship Troopers!
Serious suggestion: The Battle for Algiers
Apparently the writer for this is the same as the writer for State of Siege, which was recommended elsewhere in the replies. Neat link.