This extremely powerful piece of animated propaganda from 1933 attacks U.S. race relations. It's hard to argue with this--the Soviets were right about American race relations. Paul Robeson's voice adds great power to the message. The scenes with blacks lynched from the telephone wires like Sparatcus' army leaves a haunting image in the mind. The film does make some attempt to place race relations within the general corruptness of capitalism; after all, the overseer whips both the black and white worker. But given that African-Americans were almost entirely working class and the upper class almost entirely white, talking about race and capitalism made perfect sense.
During the Cold War, the Soviet analysis of American race relations had great importance. As the nations of Asia and Africa threw off their colonial chains in the 1950s and 60s, and as Latin American nations began to choose governments less tied to the United States, American treatment of black people proved a powerful tool in the Soviet arsenal. Why would a newly freed African nation side with the U.S? After all, their president would have to stay in a segregated motel when visiting Washington! I don't know if the Soviets sent these race-based cartoons to their allies in the developing world, but they certainly played up each racial incident. And as Mary Dudziak convincingly shows in her book Cold War Civil Rights, the knowledge that segregationist violence was hurting the U.S. in the Cold War helped move presidents Eisenhower, Kennedy, and Johnson to move more aggressively on civil rights than they otherwise would have.
Finally, the animation is pretty first-rate for 1933. Between the simple figures of lynched blacks to the expressive face of the man at the end of the film to the rich capitalist who kills the black man who won't shine his shoes, this is first-rate art as well as effective propaganda.