i recently came across a small picture on an awesome blog i follow on tumblr of two sistahs grooovin. so i researched the name Wattstax and found a film about a music festival from 1973 in LA. the film not only showcases various musicians and artists from that time period (The Staple Singers, Melvin Van Peebles, Isaac Hayes, etc.), but they also interview common black people about racism, about black male/female relationships, politics, gospel and the church, and living in LA in '73. definitely a must-see.
here's a clip from youtube:
watch the entire film here (on the link, click the red button, and then click it again after it turns green. ignore any pop-ups).