It took nearly a century, but the Oklahoma City National Memorial and Museum in north Oklahoma City is finally confronting what is known in the city as one of its deadliest race riots.

On Sept. 16, 1921, hundreds of angry citizens gathered at the foot of Whitcomb Street to protest the death of a black farmer. Several angry citizens set on fire a convenience store, then began a rampage through the low-income neighborhood, torching more than 50 buildings and killing an estimated 145 people. The Tulsa Race Riot was one of the deadliest urban rebellions in American history, with organizers said to include white supremacists and Ku Klux Klan members.

“We’re calling this what it was — a race riot,” museum CEO Gary Slutkin said Monday. “What began as a neighborhood unrest between a group of people, coupled with some agitators who did not have any compassion, began to snowball into a race riot in response to a crime that has been nearly forgotten.”

The museum is launching an investigation into the riots’ circumstances, now nearly two years after the federal government announced the artifacts were at risk of being “misappropriated.” Among those items is a carriage – the same type owned by the killer of the famous Freedom Riders in 1961 – police uniforms worn during the riot, and reportedly the mortar-filled grave of a young black girl.

Sparks flew at a museum display of the carriage in November, when a white woman loudly called out that it was not appropriate to display it, the Tulsa World newspaper reported.

“There is no justification to compare her mentality and fears to that of a half-naked corpse to run amok in the most brutal way in a neighborhood,” the museum said in a statement.

Slutkin said the exhibit was opened after a group of curators reviewed the pieces of the museum’s collection to determine how and when to properly tell the story of the violence.

The Tulsa Race Riot was considered an isolated incident in the long history of America’s racial divide. The 1935 film “From Here to Eternity” spoke of one of the most violent clashes between races in this country’s history – the razing of 50 black-owned businesses in Mississippi. But when the two-week U.S. Census of 1930, which documented the numbers of African Americans living in the country, showed the number of blacks had risen from 2.4 million to 3.2 million, the nation swallowed up the news.

It wasn’t until 2013, however, that investigators finally tracked down the allegedly murdered girl’s unmarked grave to look for clues about the extent of the killings. A 100-year-old woman walked into a Tulsa cemetery and claimed the gravestone marked a girl she did not know and believed to be 200 years old.

Records showed the victim’s parents were living in Oklahoma City at the time, and investigators soon found that another black family did in fact have a child buried there. But the coroner declared that the body wasn’t the girl, known as Eliza Thompson. And the victim’s family later sued the city, saying police had improperly dug up the grave.

A federal judge eventually ordered Tulsa to dig up the remains in order to investigate whether they were the girl’s or the parents.

“It is now our chance to share the events of that most painful time in our community’s history, with the victims’ families and with the people of Tulsa who mourn the loss of their beloved families,” Slutkin said.

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