The contemporary Mexican artistic movement known as muralism, a movement of public art that began with images painted on walls in an effort to represent Mexican national culture, is closely linked ideologically with its main sponsor, the new Mexican government elected in 1920 following the Mexican Revolution. This government promoted an ambitious cultural program, and the young revolutionary state called on artists to display Mexico's richness and possibility. But the theoretical foundation of the movement was formulated by the artists themselves. The major figures in the muralist movement, David Alfaro Siqueiros, Diego Rivera, and José Clemente Orozco, all based their work on a common premise: that art should incorporate images and familiar ideas as it commented upon the historic period in which it was created. In the process, they assimilated into their work the customs, myths, geography, and history of the local communities that constitute the basis of Mexican national culture.

But while many muralist works express populist or nationalist ideas, it is a mistake to attempt to reduce Mexican mural painting to formulaic, official government art. It is more than merely the result of the changes in political and social awareness that the Mexican Revolution represented; it also reflected important innovations in the art world. In creating a wide panorama of Mexico's history on the walls of public buildings throughout the country, muralists often used a realist style. But awareness of these innovations enabled them to be freer in expression than were more traditional practitioners of this style.

Moreover, while they shared a common interest in rediscovering their Mexican national identity, they developed their own distinct styles. Rivera, for example, incorporated elements from pre-Columbian sculpture and the Italian Renaissance fresco into his murals and used a strange combination of mechanical shapes to depict the faces and bodies of people. Orozco, on the other hand, showed a more expressionist approach, with loose brushwork and an openly emotional treatment of form. He relied on a strong diagonal line to give a sense of heightened movement and drama to his work. Siqueiros developed in a somewhat similar direction as Orozco, but incorporated asymmetric compositions, a high degree of action, and brilliant color.

This stylistic experimentation can be seen as resulting from the demands of a new medium. In stretching their concepts from small easel paintings with a centralized subject to vast compositions with mural dimensions, muralists learned to think big and to respect the sweeping gesture of the arm—the brush stroke required to achieve the desired bold effect of mural art. Furthermore, because they were painting murals, they thought in terms of a continuum; their works were designed to be viewable from many different vantage points, to have an equally strong impact in all parts, and to continue to be viewable as people moved across in front of them.