Turned away from the Carnegie Institute of Technology because she was "colored," Catlett earned a bachelor's degree in art in the mid-1930s from Howard University, a historically black institution.
She joined the Works Progress Administration, the Depression-era program that employed many starving artists, and was exposed to Rivera and his fellow Mexican muralist Miguel Covarrubias, whose politics influenced her future works.
Catlett taught art at a North Carolina high school for a time but was discouraged by the inequality in pay between black and white teachers. She left for what is now the University of Iowa, earning a master's in fine art in 1940.
Faculty member Grant Wood — best known for "American Gothic," his 1930 painting of an Iowa farm couple — mentored her. He encouraged Catlett to do as he did and use her culture and community as the subject of her art.
"I'd never been around white people in all my life except to fight with them," Catlett later said of Wood's unexpected support.
For her graduate thesis, she sculpted "Negro Mother and Child," which won first prize in the 1940 Columbia Exposition, a Chicago exhibit of African American artists.
When she was named chairwoman of Dillard University's art department in New Orleans in 1940, African Americans were not allowed in the park surrounding the New Orleans Museum of Art. Catlett got around the prohibition by having her students bused to the museum door.
In 1941, Catlett became involved with the South Side Community Art Center in Chicago, a magnet for progressive African Americans. She met artist Charles White there and after they married they moved to New York City.
She joined the faculty of the George Washington Carver School, a community learning center in Harlem run by progressives and radicals. At Carver, her "conviction that her art should be directed to the masses of working people took root," Herzog wrote in the Catlett biography.
By the late 1940s, the artist was in Mexico City and soon divorced from her first husband.
Through the print-making collective, she came to know Mora when he offered to teach her Spanish. He died in 2002.
She is survived by their three sons, Francisco, a jazz musician; Juan, a filmmaker; and David, an artist; 10 grandchildren; and six great-grandchildren.
In 1959, she became the first woman to chair the sculpture department at the National Autonomous University of Mexico, a position she held until retiring in 1975.
When the Studio Museum in Harlem staged a major exhibit of her art in 1971, the State Department granted Catlett a visa after receiving an outpouring of petitions on her behalf.
The exhibit bolstered Catlett's growing reputation as a leading artist and voice for African Americans. Many other exhibitions followed in the U.S. and Mexico, and her work is collected by major museums.
When the California African-American Museum exhibited her work in Los Angeles in 1999, Catlett told The Times: "Seeing all those people sends a message that maybe I'm doing a little bit of what I wanted to do, which is to bring African American people into museums. And I really believe that if it is something they can relate to, they will come."
Rourke is a former Times staff writer. Nelson is a Times staff writer.
Times staff writer Tracy Wilkinson contributed to this report from Mexico City.