In the 1950s, Tony Bennett watched with dismay as black musicians such as Nat King Cole and Duke Ellington were denied entry to concert hall dining rooms and hotels. The injustice he witnessed infuriated the young singer.

«I had never been politically inclined, but these things went beyond politics,» Bennett wrote in «The Good Life,» his 1998 autobiography. «Nate and Duke were geniuses, brilliant human beings who gave the world the most beautiful music it has ever heard, and yet they were treated like second-class citizens. The whole situation infuriated me.»

So when artist and activist Harry Belafonte called Bennett and asked him to join the Rev. Martin Luther King Jr.’s voting rights march from Selma to Montgomery in 1965, Bennett agreed without hesitation. He flew to Alabama and joined his allies in the fight for justice.

Bennett, who died Friday at age 96, was inducted into the American musical pantheon thanks to her velvety voice and seemingly effortless mastery of the standard songbook. But his civil rights activism is another essential part of his legacy, and he saw his entry into King’s political movement as a crucial chapter in his life.

«When the march began, I had a strange feeling of déjà vu,» Bennett wrote in his 304-page autobiography. «I kept remembering a time twenty years before, when my friends and I made our way to Germany.» While serving in World War II, Bennett’s friendship with a black serviceman was condemned by white army officers.

«Same thing in Selma – white state troopers were really hostile and had no qualms about showing it,» Bennett wrote. «There were threats of violence along the march route, from Montgomery to Selma, some of which made the evening news and really helped make the country aware of the ugliness that was still happening in the South.»

Bennett was «terrified,» he recalled, but Belafonte «stayed calm» and helped make sure everyone was focused on the road ahead. (Belafonte died in April. He was also 96 years old.)

Bennett did not walk the 54 miles. Instead, he went ahead of Montgomery so he could be there on March 24 to greet King and sing for the protesters alongside Ella Fitzgerald, Pete Seeger, Joan Baez, Sammy Davis Jr., Mahalia Jackson and others. The day after the Stars for Freedom rally, King delivered the «How Long? Not Long» speech on the steps of the Alabama State Capitol.

“I am enormously proud to have been able to participate in such a historic event,” Bennett wrote in his autobiography, “but it saddens me to think that it was ever necessary and that anyone should suffer simply because of the color of their skin.”

As the march from Selma to Montgomery came to an end, Bennett was driven to the airport by one of King’s supporters, Viola Liuzzo, a white woman from Detroit with three children. She later found out that white supremacists killed her on the way back to Selma.

Bennett became committed to the cause of racial equality in the decades that followed. He advocated for talented black artists and pushed the corporate music industry to release his records. He joined the arts boycott of apartheid in South Africa and performed for Nelson Mandela during the South African president’s first state visit to Britain.

The singer’s enduring spirit of inclusion was clear to his children, including his eldest son, Danny, who recalled a «wonderful childhood.»

In an interview with Good Housekeeping in 1995, Danny Bennett recalled «waking up to Count Basie and Duke Ellington playing in our basement.» Danny was «proud» that his father joined King’s march «before it caught on with celebrities» to publicly crusade against racist discrimination.

«He’s a good man and a good father,» Danny Bennett said.

In 2007, Tony Bennett was inducted into the International Civil Rights Walk of Fame, a walk at the Martin Luther King Jr. National Historical Park in Atlanta. Other members that year included Hollywood icon Sidney Poitier, who died last year, and Rep. Maxine Waters, D-Calif.

Five years earlier, the King Center for Nonviolent Social Change, a nonprofit organization in Atlanta, presented Bennett with its 20th annual «Salute to Greatness» award. King’s widow, Coretta Scott King, said the singer deserved the honor.

«Tony is not only one of America’s leading artists, but he was a deeply committed friend and supporter of my husband and the civil rights movement,» she said in a statement at the time. «He has continued to support the King Center’s efforts to fulfill Martin’s dream, along with many other great causes.»

Bennett, for his part, told The Atlanta-Journal Constitution that he was «over the moon». In an interview with the newspaper, Bennett reflected warmly on her friendship with Belafonte and the inspiration she drew from the latter’s example.

«Harry reassured me that we are all political animals when injustice happens,» Bennett said. «We are all a tiny speck on the face of the universe. Every person on this planet is important and should be equally respected.»