I watched the following films from 1975:
Robert Altman's Nashville is a panoramic black comedy which follows 24 characters for 5 days in the country music capital of America. It's the purest expression of Altman's signature style - multiple characters, overlapping dialogue, reflection of real life through comic exaggeration. There is no lead character or central narrative - each of the two dozen characters are equally important. It's like a collection of short stories which, taken together, form a remarkably cohesive whole. It
reflects the paranoid political and cultural climate of post-Watergate, post-Vietnam America.
It contains numerous references to political assassination and was released a few months before the two failed attempts to assassinate President Ford.
The A.V. Club called it the film that defined the 70s.
Robert Altman Primer
Roger Ebert's review
Josh Modell's review