TULSA — The mayor was about to take a bite of his pecan waffle at his favorite breakfast spot when a white woman stalked up to his table, pointed her finger and lit into him about his decision to reopen an investigation into a century-old race massacre.

“You are doing this to make white people feel bad,” the woman told G.T. Bynum as he and his wife and two children were eating at Phill’s Diner on a recent Sunday morning.

The waitress tried to get the woman to sit down, Bynum said, but she refused, angered by the city’s plan to dig for bodies from the 1921 massacre, one of the worst episodes of racial violence in U.S. history. The excavation at Oaklawn Cemetery, where ground-penetrating radar revealed a “large anomaly” that could be a mass grave, is scheduled to begin April 1.

Bynum, a white Republican in deeply red Oklahoma, tried to explain the unresolved questions about a rampage historians believe left as many as 300 black people dead. As other customers looked on, he said he would not back down from trying to find answers to what happened.

“Usually, my M.O. in a situation like that is to listen to the person and let them vent,” Bynum recalled. “After it went on for five or six minutes, I felt I had to interject and point out the history of what happened. I pointed out my family were white people who lived here in 1921. I’m not trying to make white people look bad. I’m just trying to find the truth. I said, ‘If your ancestors had their entire neighborhood burned down, and your neighbors were murdered, wouldn’t you want to find out what happened to them?’”

At 42, Bynum is an unlikely champion of revisiting Tulsa’s harrowing past. Like the furious woman in the diner, he has deep roots in Tulsa. His grandfather, Robert LaFortune, served as mayor from 1970 to 1978. His great-great grandfather, R.N. Bynum, was Tulsa’s second mayor in 1899.

Bynum’s father, who owned an oil-field machining company, also was president of the Tulsa Historical Society. On weekends, G.T. would go with his dad to the Gilcrease Museum to help categorize information stored by the historical society.

But Bynum said he never heard about the massacre growing up. “My parents didn’t hear about it until 2000,” Bynum said. “My dad, who was president of the historical society, didn’t hear about it. The first time I heard about the massacre was when my cousin Bill was running for mayor” in 2001.

Bynum volunteered to drive him around to campaign events. “We were at a forum,” he recalled, “and someone mentioned that there had been a race riot in Tulsa. … And that bombs had been dropped from airplanes on Tulsans.

“I thought that was insane. No way something like could have happened in Tulsa. And I started looking into it and found it had been true. It was a big shock. You don’t think you could live in a place, and no one would talk about it at all. They never brought it up in our history course in high school. It never came up in meetings at the historical society.”

Now millions of Americans are learning about the massacre through HBO’s hit series “Watchmen.” As Tulsa prepares to mark the 100th anniversary of the violence next year, it will be taught in Oklahoma public schools for the first time.

The violence began on May 31, 1921, after a black teenager working as a shoe shiner in downtown Tulsa was arrested and accused of assaulting a white woman.

His arrest sparked a confrontation between “angry white vigilantes gathered at the courthouse intent on lynching the shine boy” and armed black men intent on protecting him, according to a 2001 report by the Oklahoma Commission to Study the Tulsa Race Riot of 1921.

After a shot was fired, white mobs descended on Tulsa’s all-black community of Greenwood, known as “Black Wall Street” for its affluence. “By the time the violence ended,” according to the Oklahoma Historical Society, “the city had been placed under martial law, thousands of Tulsans were being held under armed guard, and the state’s second-largest African American community had been burned to the ground.”

Witnesses told stories of black bodies being thrown in the Arkansas River and dumped into mass graves.

For decades, few white people would talk about what happened. Black survivors spoke about it in whispers. Thousands of people who lost their homes and businesses in the fires were never compensated. No one was arrested.

The 2001 report represented Oklahoma’s first real effort to account for the massacre. But city officials ignored the commission’s recommendation to conduct a “limited physical examination” of Oaklawn Cemetery for a possible mass grave and consider reparations for massacre survivors or their descendants.

In 2018, after The Washington Post published a story about the unsettling questions surrounding the massacre, Bynum announced he would reopen the investigation.

Some descendants of massacre survivors were astonished by Bynum’s announcement.

“He is the first mayor in almost 100 years who did something,” said J. Kavin Ross, who wrote for the Oklahoma Eagle, Tulsa’s black newspaper, about his search for mass graves.

Bynum acknowledged his decision isn’t universally popular in a conservative city of 400,000, where almost two-thirds of residents are white and just 15 percent are black. The search for a mass grave is unfolding as Bynum runs for a second term.

“I’ve heard that some people say it’s unusual for a white Republican mayor to be focused on this,” Bynum said. “I don’t view it from a partisan standpoint at all. I view it as basic decency.”

Bynum has long prided himself on political pragmatism. After he became mayor in 2016 by defeating a Republican incumbent, he delivered a TED Talk on replacing partisanship with policy. In it, he joked that his name reminded people of a circus promoter and that his emphasis on data-driven decision-making had transformed him into “a guy with the raw animal magnetism of a young Orville Redenbacher.”

Tulsa’s City Hall occupies a spectacular glass high-rise that dominates the skyline of the former oil-boom town. Inside the mayor’s office, Bynum often works at a conference table his grandfather used when he was Tulsa’s street commissioner from 1964 to 1970. One of LaFortune’s first votes as commissioner “was to desegregate public facilities in Tulsa,” Bynum said.

His grandfather never told him the story about that vote. “I read about it in an old newspaper article,” Bynum said.

He considered himself ideally suited to absorb any backlash from the search for mass graves because his relatives lived in Tulsa during the massacre and “my family is also buried in Oaklawn Cemetery.”

When he first learned about the rampage in 2001, Bynum wanted to know whether anyone in his family had been involved in the violence. “I asked both my grandfathers about it,” Bynum said.

His maternal grandfather told him the LaFortunes had just moved to Tulsa and, as Catholics, feared the Ku Klux Klan. “They were holed up in their apartment” during the massacre, Bynum said.

His paternal grandfather said he’d been told by his father they’d sheltered black friends in their house. Bynum also noted “there were a lot of Bynums in Tulsa at the time,” and he doesn’t know what all of them were doing.

Tulsa remains highly segregated. Last year Human Rights Watch issued a scathing report on the city’s inequities and the way black Tulsans are targeted by police. In January, Bynum appointed the first black police chief in Tulsa’s history.

The month before, during a public meeting where scientists announced they had found what could be evidence of mass graves in Tulsa, the mayor was peppered with questions from skeptical African American activists insisting the city pursue justice.

Bynum, in a gray suit, green tie and horn-rimmed glasses, assured the crowd at George Washington Carver Middle School he wanted justice, too. “I’m not here to defend anything wrong the city has ever done on this,” Bynum said. “We will follow the truth where that takes us.”

“It is very important for us to continue this search” for bodies, he said. “If they are there, we are going to find them.”

Dewey Follett Bartlett Jr., the incumbent mayor Bynum defeated in 2016, said he believes most people in Tulsa — white and black — want the question of mass graves resolved so the city can move forward.

“Either find them or, if nothing is found, hopefully it might be the end of the investigation, and we look forward to recognizing the 100th anniversary of the race riot and the resulting massacre and move on,” Bartlett said.

The angry woman at Phill’s Diner expressed a different opinion. “She kept using the term, ‘the blacks,’ which was the uncomfortable part for me because my kids had never heard someone talk about African Americans using a term like that,” Bynum said.

When the woman finally walked back to her table, the mayor’s 13-year-old son and 10-year-old daughter looked down at their cold pancakes, embarrassed by the outburst.

“I said: ‘Hey, look at me. Doing the right thing is not always popular. Some people will get mad at you. When you do the right thing, not everybody is there to tell you that you are doing the right thing,’” Bynum recalled. “Then we went on with our breakfast.”

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