Her daughter Jenny Lumet, screenwriter and producer, told The New York Times that she died at her home in Santa Monica, California, due to heart failure. Buckley is best remembered for her impactful writing and journalism.

Born on December 21, 1937, in Pittsburgh, Pennsylvania, she grew up in Brooklyn and Los Angeles. Buckley chose a different career path from her mother and earned a bachelor’s degree from Radcliffe College in Massachusetts in 1959. Her journalism career began shortly after that.

She was an intern in Paris with Marie Claire magazine, then returned to the United States and worked as a counselor with the National Scholarship Service and Fund for Negro Students. Three years later, Buckley was hired as a writer for Life Magazine, where she wrote newspaper and service wire articles, per the New York Times.

Nearly two decades later, Buckley was married and later divorced from film and television director Sidney Lumet, with whom she raised their two daughters. She then resumed her journalism career as a freelance writer, contributing to The New York Times, The Los Angeles Times, The Daily News, and Vogue.

In 1986, Buckley became a published author when she wrote her first book, “The Hornes: An American Family,” chronicling her family history after finding hundreds of artifacts dating back six generations.

“It all unfolded like a detective story — here is what was happening in 1875, there’s what went on in 1895,” she told The Los Angeles Times when the book was published. “And then to read Black American history, as I did extensively, and put that on top of it; that’s an exciting experience.”

Three decades later, Buckley revisited her past with her 2016 book, “The Black Calhouns: From Civil War to Civil Rights With One African American Family.” The book examines historical events and political movements that impacted both sides of her family: one side, enduring the Jim Crow era in Atlanta and the other experiencing the Harlem Renaissance in New York City.

Buckley also published, “American Patriots: The Story of Blacks in the Military From the Revolution to Desert Storm“ in 2001, and her recent book, “Radical Sanctity: Race and Radical Women in the American Catholic Church,” published in 2023.