This work Is the central panel of a series of mural paintings, "Portrait of America" produced for the New Workers School in New York. In these paintings, the history of the United States is depicted, from colonial days to the War of Independence and the Civil War, and on toward the rapid development of modern industry, world crisis, the appearance of Nazism, etc. up until 1933 when this work was produced.
Of the 21 original panels, 8 still exist. The faces of many leaders can be seen, the leader of the Russian revolution, Lenin, flanked by Marx and Engels in the center of the painting, the Secretary General of the Russian Communist Party, Stalin and the exiled revolutionary, Trotsky at their side, and in front of them, the German woman revolutionary Luxemburg. In the front, America's socialist movement leader, Lovestone, who commissioned this mural painting and was the founder of the New Workers School, is painted with a flag containing the words of Lenin,"WORKERS OF THE WORLD UNITE! ".
Rivera said that in "Proletarian Unity, he had drawn the "progressive side of American development in the unity of proletarians and in the new social establishment, represented by the group of figures consisting of the firmly united fathers of socialism and the leaders of international revolutionary movements. This mural painting represents the peak period in the life of Rivera, who was good at group expression.
(Source: Selected Works from the Collection of Nagoya City Art Museum, 1998, P. 53.)