For the august age of civil rights documentaries comes this serious, confrontational 1967 Oscar nominee, selected last year by the Library of Congress and the National Film Preservation Board for the National Film Registry. It’s an invaluable snapshot of an all-American place and time caught in the ragged throes of cultural growth. Shot by Bill Jersey in 1966 Omaha, the doc records the travails of Lutheran pastor William Youngdahl, transplanted from an integrated parish in New Jersey to a segregated one in Nebraska. Quietly appalled, Youngdahl launches a career-wounding campaign within his church to integrate it with a black ministry. Jersey and soundie Barbara Connell focus in on the strategic debates, and you never saw so many flabby, crew-cut Midwestern white guys earnestly and pure-heartedly wrestle with the reality of racism in your life. Still, the hour-long movie, produced by something called the Lutheran Film Associates, is stolen by one Ernie Chambers, a black barber who metes out ideological drubbings in a measured rant as he simultaneously cuts heads, and whose position is so staunch and rigorous it’s a shock to learn that he was a few years later elected to the Oklahoma state senate. The supplements include an expansive new interview of Chambers by Jersey, in which the graying tiger bids farewell to a legislature that finally passed a law to kick him out.