American movies didn’t wait for Angelina Jolie and Michael Moore to develop a social conscience. One of the sobering lessons of the new anthology from the National Film Preservation Foundation, “Treasures III: Social Issues in American Film 1900-1934,” is that the pictures of the early 20th century were in many ways more open to the social and political world: people struggle to make a living, fight against disadvantages and prejudices and are confronted with confounding moral choices on a daily basis.

Among the topics broached in the 40-odd films, both short and feature-length, in this four-disc set are abortion, unionization, interracial marriage, the rights of women, immigration, workplace safety, homelessness, public education and predatory lending practices.