Timeline: Tracking Oklahoma's white supremacist roots over more than a century

Historians and scholars say white supremacy is a bedrock of Oklahoma’s founding. “It’s intrinsic,” said Quraysh Ali Lansana, a visiting professor at the University of Tulsa. “It’s in the water.”

Most of what became Oklahoma was promised by U.S. officials to tribal nations in exchange for ceding their homelands. Some Southeastern tribes brought enslaved African Americans with them on their move west. White settlers flooded into the territory and pressured federal officials to make more land available.

1866: Treaties signed between U.S. officials and leaders of the Cherokee, Chickasaw, Choctaw, Muscogee and Seminole nations formally end slavery in Indian Territory, which would later become part of Oklahoma. The treaties also granted formerly enslaved people and their descendants certain citizenship rights in the Five Tribes, but only the Cherokee Nation fully extends that recognition today.

1887: Congress starts it 20-year effort to break up tribal reservations into individual pieces of land allotted to tribal citizens, opening lands for white settlement and paving the way to Oklahoma statehood.

1907: Oklahoma is admitted into the United States. The first law passed by the new state legislature barred Black people from riding on the same streetcars and trains as white people. The state becomes known for enacting some of the most discriminatory laws outside of the Deep South.

1920s: A series of murders known as the Osage Reign of Terror occurs in northern Oklahoma. White people kill an unknown number of Osage Nation citizens to gain tribal members’ lucrative mineral and land rights. The 2023 major motion picture “Killers of the Flower Moon” portrays one high-profile case.

1920s: Membership in the Ku Klux Kan surges, with members at every level of Oklahoma government. Anti-Black sentiment grows around the country after World War I.

1921:The Tulsa Race Massacre, regarded as one of the worst acts of racial violence in the U.S., occurs after rumors start of a Black man harming a white woman. White Tulsans destroy the city’s thriving Greenwood neighborhood, killing as many as 300 African American residents. An untold number of more Black families fled the city after their homes and businesses are burned and looted.

1948: The U.S. Supreme Court rules Oklahoma must provide a Black law student the same educational opportunities as white students at the University of Oklahoma. Instead of allowing Ada Sipuel to enroll in classes after the ruling, state officials set up a separate law school for her in the Capitol. They eventually relented after she planned to appeal again to the Supreme Court.

1950s to `60s: The push to end segregation takes hold in Oklahoma and across the U.S. In Oklahoma City, civil rights leader Clara Luper helped organize a series of lunch counter sit-ins that led to the end of legal segregation in public spaces.

1972: A federal judge rules Oklahoma City schools continued to segregate students by race, leading to a busing plan that generated huge backlash among white parents and residents. Police break up fights outside some schools. The “white flight” from Oklahoma City schools continued for decades.

1995: Timothy McVeigh, an anti-government extremist, detonates a bomb outside of the Alfred P. Murrah Federal Building in downtown Oklahoma City. The bombing leaves 168 people dead and becomes the deadliest act of domestic terrorism in the U.S. The incident becomes a source of inspiration for people who plan or commit racially motivated violence, according to a 2020 ABC News investigation.

2001: Oklahoma lawmakers formally recognize the destruction of the Tulsa Race Massacre and acknowledge the state benefited from a “conspiracy of silence” that existed around what happened for decades. The law recognizes the “moral responsibility on behalf of the state of Oklahoma and its citizens that no race of citizens in Oklahoma has the right or power to subordinate another race today or ever again.”

2020: The Supreme Court rules the Muscogee Nation Reservation still exists in eastern Oklahoma, meaning the state does not have the power to prosecute tribal citizens on those lands. The ruling is later applied to eight other tribal reservations. Gov. Kevin Stitt criticizes the ruling as unfair because it divides the state by race. It is based on citizenship, not race.

2022: Lawmakers pass House Bill 1775, a controversial law that limits how schools teach certain concepts about race. Critics say the law could lead entire chapters of Oklahoma history to be erased from textbooks.

2024: The New York-based Anti-Defamation League, which tracks the spread of hate, has records of more than 550 incidents of hate, extremism, antisemitism or terrorism in Oklahoma over the past five years.