The Rev. Ralph Abernathy, right, and Bishop Julian Smith, left, flank Martin Luther King Jr., during a civil rights march in Memphis, on March 28, 1968. (Jack Thornell/AP)

This year has seen a number of race-focused documentaries that seem especially relevant following a historically contentious election. The most comprehensive of the bunch — "Black America Since MLK: And Still I Rise" — concludes Tuesday night on PBS. In the four-hour series, Harvard professor Henry Louis Gates Jr. reflects on the last 50 years of black history and the stark racial divide that emerged following the election of the country's first African American president.

With so much ground to cover, "Black America Since MLK" is less exacting than Ava DuVernay's "13th," which examines mass incarceration's disturbing legacy (and features Gates as an expert), or as detailed as Ezra Edelman's "O.J.: Made in America," which explored the role of race in O.J. Simpson's rise to fame and the conflicting reactions to the former football star's acquittal in the murder of his ex-wife. But "Black America Since MLK" benefits from airing just after Donald Trump was elected president, and it helps put some of the fears many African Americans have as a result into historical context.

Part one of "Black America Since MLK," (which aired last week, but is free to stream on PBS's website) reminds us that "Make America Great Again" is a spin on a campaign slogan Ronald Reagan used in 1980. In the documentary, Gates notes that Reagan's message was a cause of concern for many African Americans, who feared policies that would reverse progress achieved during the civil rights era. "Black America Since MLK" also recalls voter suppression efforts and the backlash against affirmative action in late '7os.

In an interview, Gates said the series, which began production two years ago and finished earlier this year, seems "eerily prophetic." Like many in the media and television landscape, Gates expected Clinton to win the election.

"Instead, it's Donald Trump and so many of us are concerned about sustaining the rights that our people have accrued with great pain and effort over the last 65 years," Gates said.

In 2013, Gates examined a longer period in African American history with "The African Americans: Many Rivers to Cross." The six-part series traced the journey of African Americans from slavery to President Obama's historic election and won a News and Documentary Emmy Award for outstanding long form historical program. Following that success, Gates said PBS asked him to plan three more series and he came up with a list of 10 ideas. "Black America Since MLK" wasn't even on it — Gates said he got the idea from his friend, American Express chief executive Kenneth Chenault, who encouraged him to look at the last 50 years.

"He said that's the most pivotal time in the history of race in America, and the most pivotal time in the history of African Americans in America," Gates recalled. It also reflects Gates's own lifetime — he was born in 1950.

"Black America Since MLK" doesn't just reflect on politics and social policies — it also recalls the contributions of black Americans to pop culture. The first half recalls shows such as "Soul Train," "The Jeffersons" and "Good Times." The series also describes how James Brown captured the spirit of black empowerment movement with his 1968 funk anthem "Say It Loud — I'm Black and I'm Proud," and the late soul legend's controversial endorsement of Richard M. Nixon for president. DuVernay appears to talk about the significance of Public Enemy's "Fight the Power" and the emergence of so-called gangsta rap. Tuesday's installment features Gates interviewing Shonda Rhimes.

"No one can talk about American popular culture without thinking about black culture," Gates said. "The impact has been so grand and transcendent — the way we talk, the slang we use, the music that we listen to. … I wanted to remind people of how thoroughly integrated our culture is."


President Obama greets audience members after giving a speech on immigration reform in El Paso, in May 2011. (Charles Dharapak/AP)

Tuesday's installment, titled "Keep Your Head Up/Touch the Sky," recalls the aftermath of Hurricane Katrina and features footage of then-Sen. Barack Obama visiting New Orleans with former president Bill Clinton. It also explores Obama's historic 2008 election and the racial divide that followed his reelection. The last segment looks at Black Lives Matter and draws a parallel between that movement and the civil rights era.

"No one thought that when we would be celebrating the reelection of the first black president, we would also see the rise and the necessity of a new civil rights movement under the banner of Black Lives Matter," Gates said.

The series features a sequence of police violence against unarmed black men and women, after which Gates declares that "black Americans have come together, united by a shared sense that despite all the progress we've made we remain vulnerable in our own country."

But "Black America Since MLK" ends on a hopeful note. "What stands out to me most is the strength, the willingness seen time and time again to fight against the odds, to stand and be counted no matter the risk," Gates says in the series. "Looking back, seeing how hard we've fought, how far we've come, it fills me with hope."

The last image sees Gates standing on the Edmund Pettis Bridge, the site of brutal 1965 attacks on nonviolent civil rights protesters that led to a historic march in Alabama from Selma to Montgomery, and galvanized the passage of the Voting Rights Act.

Gates told The Washington Post that he remains optimistic. "I'm hopeful, but I'm also aware that we have to be vigilant."

Part 2 of "Black America Since MLK: And Still I Rise" (two hours) airs Tuesday at 8 p.m. on PBS (check your local listings).  

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