Socialist Realism was considered the official style of art during the era of the Soviet Union (1922-1991), especially during Joseph Stalin's reign (1941-1953). The aim of socialist realism generally attempted to portray the positive elements of a socialist society. The art emphasized class equality, communal harmony and the overcoming of capitalist oppression. All of this was achieved without abstract representation. The standard definition of socialist realism is attributed to Aleksandr Gerasimov, a Russian painter, who deemed it to be: "Realistic in form, Socialist in content."
One dominant theme of Marxist aesthetic theory stresses the importance of art to educate its audience. Accordingly, art should educate the viewer in the history of the proletarian struggle against the capitalist mode of production. It should also stress such themes as social harmony, social justice and liberation from class oppression. Since art is educational, the content of the artistic object must be direct and forceful in its representation.
In Mexican mural art, the plight of workers within a capitalist structure is portrayed. The murals of Diego Rivera and José Clemente Orozco often represent workers struggling in inhuman factory conditions. Often these murals are painted in dark hues and feature billowing clouds of smoke. Other murals may portray workers in a field whose bodies are bent in the act of cutting grain with a scythe. Such Marxist art may also portray the benefits of work within a socialist structure.
Another recurring motif in Marxist art is that of the proletarian hero who overcomes hardship and class oppression to teach others of the glory of the Socialist revolution. Whether the hero was a scientist, writer or factory worker, he became a model of the ideal citizen for others. The portrayal of this type of proletarian hero was most dominant within the literature produced during the era of Soviet rule.