Bijan C. Bayne is an author and cultural critic who is producing a docuseries about Kareem Abdul-Jabbar.

In the groundbreaking 1967 film “Guess Who’s Coming to Dinner,” Sidney Poitier’s character, a Black intellectual and physician named John Prentice, tells his future father-in-law, portrayed by Spencer Tracy, that his fiancee, Joanna, whom he met during her vacation in Hawaii, “feels that all of our children will be president of the United States and they’ll all have colorful administrations.” A full four decades later, on Nov. 4, 2008, a man from Hawaii named Barack Obama, who had been born to a Kenyan economics graduate student and Stanley Ann Dunham, a White anthropology student, was elected the first Black president of the United States.

Poitier, who died Thursday at 94, was this country’s most significant Black male role model between the years Jackie Robinson played Major League Baseball and Obama governed the nation.

In the 1950s and ’60s, with all the influence that films bore on society and popular culture, Poitier was the first marketable Black male superstar and romantic lead. He helped the movie industry pivot from previous portrayals of Black men as butlers, shiftless country folks and frightened Pullman porters to the accomplished and confident archetypes he embodied (and in the process became one of the era’s biggest box office stars).

This was by intent. Poitier was born by surprise in Miami and raised in Bahamian poverty. Until he moved to Nassau at 10, he hadn’t seen a car, a refrigerator, electricity or indoor plumbing — circumstances hardly likely to set him up as an American pop-cultural trailblazer but which surely informed his beliefs about human dignity.

At 15, he moved to Miami, then landed in New York City. After lying about his age to enlist in the Army during World War II (when he was 16 — a first bit of acting), he was assigned to work in a psychiatric hospital. There, he became upset at the manner in which patients were treated. Poitier feigned his own mental illness (a second go at dramatic pretense) to broker a military discharge and returned to odd jobs in New York.

A newspaper ad led him to try out for theater roles, but his thick accent and inability to sing limited his prospects. Undaunted, he labored on his diction — his West Indian tonality eventually lending an air of panache to his upright movie characterizations.

His breakthrough lead role, for which he drew on his own hospital experience, came as a doctor treating a bigoted gunshot wound victim in 1950′s “No Way Out.” From there, he advanced through a medley of lead and supporting screen and Broadway roles, including an Oscar-winning turn as a jovial handyman in 1963’s “Lilies of the Field.” In 1967 alone, in addition starring in “Guess Who’s Coming to Dinner,” he gave award-worthy performances in “To Sir, With Love,” about a West Indian engineer teaching life lessons to high school toughs in London’s East End, and “In the Heat of the Night,” about a Northern Black detective thrust into a Southern murder investigation, with a bigoted town sheriff as his sleuthing partner.

Such was the extent of Poitier’s type-casting as the spotlessly perfect Black man that some younger activists of the 1960s civil rights movement bristled at the perceived impossibility of his characters. Away from the screen, however, Poitier became a pivotal funder and supporter of the fight for racial justice, which drew him close to the Rev. Martin Luther King Jr. and to fellow West Indian actor and activist Harry Belafonte.

But just as much as Poitier’s real-world activism, his movie roles were crucial to changing White American society’s perception of Black male fortitude. In his famed autobiography, Malcolm X praised Poitier for wearing his hair in its natural state. And in “In the Heat of the Night” — in one of the most memorable scenes in movie history — his face-slap of a racist White textile tycoon sent stunned hushes and hurrahs through theaters across the country.

The film’s tycoon devolves into tears, mourning the changing times. Yet imagine, once the initial astonishment of “the slap” died down, the thrill Black moviegoers must have felt that a Poitier character had finally doffed his angel’s wings.

In a world of Barack Obamas and Kamala Harrises, some might argue that we don’t need another Sidney Poitier. But without him, many filmgoers of previous generations might never have imagined an educated, Black authority figure — or the political and pop-cultural landscapes now driven by the power and creative energy of Black men and women.

In an era when ethnic discrimination in the workplace, politics and education was based largely on deeply rooted stereotypes, Poitier stood above it all. Few actors have ever been as culturally significant as the one who once said: “I had chosen to use my work as a reflection of my values.”