The wonderful true story told in “Rosenwald” is a terrific history lesson, and an inspirational portrait of how one person can make a difference. And in a sly way, it’s also a rebuke — or maybe a challenge — to the new generation of freakishly rich people.

The story of Julius Rosenwald stands in violent contrast to the profile of, say, the loathsome millionaire who hiked the price of the AIDS drug he now owns, or the pumpkin-haired TV star who has enchanted this country’s Republicans.

The wealthy people of olden times weren’t all peaches and cream, but Rosenwald’s attitude — seen in vintage clips — was that any rich person is enormously lucky, and has a responsibility to give back.

The film, directed by expert chronicler of Jewish-American history Aviva Kempner (“The Life and Times of Hank Greenberg”), is not so much a bio of Rosenwald as a chronicle of his effect on African-American life.

Rosenwald, born in 1862 to a German immigrant family, became chief of Sears, Roebuck, the Amazon.com of its era. His interest in social disparity was keen, and — after some artful nudging from Booker T. Washington — Rosenwald began a program that built thousands of bright new elementary schools in the Jim Crow South.

The Rosenwald schools were also supported by donations from the impoverished communities, which meant locals were invested in their success.

Kempner’s interviews with former Rosenwald-school students are a moving tribute to how much these places meant: the roster includes Maya Angelou, Congressman John Lewis, newspaper columnist Eugene Robinson, and director George C. Wolfe. They speak warmly and with amazing clarity about their experiences.

The film gets over-extended, but only because the story continues in ways too fascinating to resist recounting. For instance, in 1928 Rosenwald founded a fellowship to support Southern artists and scholars.

The recipients of this fund read like a pantheon of African-American achievement: Jacob Lawrence, Langston Hughes, Zora Neale Hurston, Marian Anderson, Ralph Ellison, and James Baldwin are among the names.

Kempner has rightly added to the legacy of a philanthropist with this film. Time for the new super-rich to consider their legacies as well as their priorities, and spread the wealth around — there may be a documentary profile in it.

“Rosenwald” (3 stars)

Wonderful documentary about Julius Rosenwald, the Sears, Roebuck executive who gave away millions to build African-American schools throughout the South in the early 20th century. The true story is fascinating, and the first-person testimonials are stirring.

Rating: Not rated; probably PG for subject matter

Showing: Sundance Cinemas Seattle