Clasping white-gloved hands, swaying side to side, the singer’s exaggerated pale lips stand out against his jet-black face. At first glance, actor Al Jolson crooning “My Mammy” in The Jazz Singer depicts an offensive image of a black performer.

“It’s pretty much impossible for a 21st-century viewer to look at that film and not squirm. How could anyone at the time not see Jolson’s performance as a gross stereotype?” wondered Martin Berger, UC Santa Cruz professor of history of art and visual culture. But while critics debated aspects of the first feature-length talkie, Jolson’s makeup didn’t spark controversy among whites or blacks when the box-office hit premiered in 1927.

Berger has long been intrigued by how subtle social forces affect Americans’ perceptions, and by the way historical events are represented—and later remembered differently—through such media as movies, paintings, or photographs.

In his analysis of news photos from the civil rights movement, published in his books Seeing through Race and Freedom Now!, Berger concluded that certain, oft-seen images became canonical scenes because they reinforced prevailing preconceptions of violent Southern whites victimizing powerless blacks.

By selecting a small subset of photos showing protestors confronted by police batons, firehoses, and attack dogs, editors emphasized white power and black passivity. Photos depicting black agency or courage—such as Emmett Till’s great uncle pointing out the teenager’s torturers while testifying in a Mississippi courtroom—rarely made the mainstream media. Berger contends that such selective documentation built white support for social change but had the unintended effect of limiting the extent of reform.

For his current book project, Inventing Stereotype, Berger focuses on the 1920s. Besides spawning The Jazz Singer, the decade saw vigorous debate about the nature of race as a biological or cultural category. Into this debate came the modern concept of stereotype, recast by prominent journalist Walter Lippmann as a social shortcut for perceiving something outside one’s experience. Lippmann’s idea of stereotype quickly took hold throughout American society—and never let go.

With a fellowship from the National Humanities Center, Berger is now examining stereotype through the works of artists such as Archibald Motley Jr., and Eugene O’Neill, who were both acclaimed and derided for their depictions of black culture. Berger suspects that past arguments about whether specific artworks are stereotyped will inform the deeper debate about race. “The controversial works [of art] are much more interesting and revealing of the boundary zone where racial identity is being resolved,” he said.

In the end, Berger hopes to explain why our interest in racial stereotype endures: “I want people to understand that stereotype isn’t a self-evident thing. Stereotype is a social construction produced in a particular moment.”