
Pan American Unity Mural, 1940 By Diego Rivera
“My mural will picture the fusion between the great past of the Latin American lands, as it is deeply rooted in the soil, and the high mechanical developments of the United States.” – Diego Rivera. Source
Photo Credit: City College of San Francisco
The San Francisco Museum of Modern Art (SFMOMA) and the City College of San Francisco (CCSF) have announced plans to display Diego Rivera’s massive mural, “Pan American Unity,” at a major exhibition of the artist’s work in 2020. The mural is considered one of the most important works of public art in San Francisco.

Rivera and Pflueger, 1940
By Peter Stackpole. Source
Photo Credit: City College of San Francisco
The 74-foot-wide, 22-foot-high masterpiece was commissioned under the auspices of the 1939-40 WPA and the Golden Gate International Exposition held on San Francisco’s Treasure Island, itself a creation of the New Deal’s PWA and the WPA.
Rivera was among dozens of artists participating in Art in Action, a live exhibit at which fairgoers could watch paintings, sculptures, weavings, and frescoes in the making in an airplane hangar that served as the Exposition’s Palace of Fine Arts, a gallery and studio.
The prominent San Francisco architect Timothy Pflueger, an organizer of the Exposition, invited Rivera to participate. In a letter to Pfleuger, Rivera happily accepted “ . . . on the condition that I be permitted to make this my personal contribution toward the promotion of good will between our countries and because of my great affection for my friends in San Francisco who made my previous stay such a pleasant one.”
“For years I have felt that the real art of the Americas must come as a result of the fusion of the machinism and new creative power of the north with the tradition rooted in the soil of the south, the Toltecs, Tarascans, Mayas, Incas, etc., and would like to choose that as the subject of my mural,” he wrote.

Rivera painting at Golden Gate International Exposition, 1940
Watch the (silent) video of Rivera and other artists working at the 1940 Golden Gate International Exhibition.
At the time, Pflueger was designing the Science Building for the new San Francisco Junior College (now City College of San Francisco). Pflueger also projected a Grand Library building where Rivera’s mural would be permanently installed once the fair closed. Because the mural would need to be portable, Rivera painted the giant buon fresco on ten steel-frame panels. It weighed 20 tons.
The mural is a sweeping panorama of the Bay Area, and interweaves images of Western industrialization and indigenous cultures. Rivera and his assistants were still working on the massive mural when the fair closed in September 1940. In December more than 25,000 people crowded into the hangar to view the finished work. The panels were then packed into five crates and moved to storage.
Because of wartime austerity, the Grand Library Pflueger had designed for City College was never built. Pflueger died in 1946. In 1961, his brother, Milton, arranged to shoehorn the Pan American Unity mural into the lobby of the college’s Little Theater, where it has resided ever since in a confined space.

Detail of Unity Mural
“It is about the marriage of the artistic expression of the North and of the South on this continent.”—Rivera
Photo Credit: City College of San Francisco
Plans are underway to move the mural to the college’s new Performing Arts and Education Center, where it will be visible from the outside through the building’s glass façade.
Upon hearing of plans to move the masterpiece, SFMOMA approached the college about showcasing it as part of a 2020 Rivera retrospective. In return, SFMOMA will underwrite the costs for the moves and the conservation of this great work.