The sorrow and death of the Trail of Tears were still fresh when a band of Muscogee (Creek) people gathered by an oak tree in 1836 to deposit the ashes of the ceremonial fires they had carried across America and begin a new home in the West. It was called Tulasi, or “Old Town.” Tulsa.

What followed were decades of betrayals, broken treaties and attempts to legislate and assimilate tribes out of existence. Then this week, the Supreme Court confirmed what the Muscogee (Creek) Nation has long asserted: That this land was their land.

“It’s so momentous and it’s immense,” said Joy Harjo, the U.S. poet laureate and a Muscogee (Creek) Nation member who lives in Tulsa. “It marks a possible shift. Not just for Muscogee Creek people, for all Native people.”

The court’s 5-4 declaration last week that much of Tulsa and eastern Oklahoma had long been a reservation of the Muscogee (Creek) Nation was seen as a watershed victory for Native Americans’ long campaign to uphold sovereignty, tribal boundaries and treaty obligations.

For Muscogee citizens, who make up the country’s fourth-largest Native American tribe, it was also something deeply personal, a thoroughly American moment that rippled across time, connecting ancestors forced to leave their homes in the Southeast with future generations.

“The impact is not only going forward,” Harjo said. “It’s going backward, all the way through the trail to Georgia and Alabama, where it resounds. It goes out in all directions.”

It brought feelings of relief, joy and vindication, mixed with older pains.

“It made me cry,” said Jason Salsman, the tribe’s press secretary. “It was a powerful moment, one I wasn’t ready for. It brought out emotions you didn’t know would be there. It was just a promise kept. We know the history of promises that have been broken. I still get chills thinking about it.”

The Muscogee (Creek) Nation, which has 86,100 enrolled members, stretches across 3 million acres of rolling hills, grasslands, small towns and cities across 11 counties in eastern Oklahoma. Sprinkled across that land are more than a dozen ceremonial grounds where citizens meet to tend sacred fires and participate in stomp-dance ceremonies.

“We experienced genocide, assimilation, colonization, conversion policy by the government,” said Amos McNac, 77, a justice on the Nation’s Supreme Court and heles-hayv, a medicine man. “We’ve survived. We still have our culture and our tradition.”

Much of that Nation’s history and even its name bear the imprint of America’s colonial legacy.

“Muscogee” is the name of their language and the name of the confederacy of tribes that once sprawled across much of Alabama, Georgia and northern Florida in a system of interlocking tribal towns with their own land and political structures. “Creek” was the name used by white settlers because they lived near water.

The Nation is one of the Five Tribes, along with the Cherokee, Choctaw, Chickasaw and Seminole, who were forced to leave their homelands in the 1830s by President Andrew Jackson and set off on a series of devastating treks west that killed thousands.

Today, the other members of the Five Tribes have similar arguments for federal recognition of their treaty lands in Oklahoma.

“You don’t know all of American history without knowing our history,” said Suzan Shown Harjo, a Cheyenne and Creek activist who received the Presidential Medal of Freedom in 2014.

The history of treaties between tribes and the United States is rife with coercion and broken promises, and activists said the court’s decision was remarkable for doing something seemingly simple: Holding the United States to the promises it had made to tribal nations.

The court’s decision brought a mix of acceptance and confusion from non-Natives across Oklahoma. The mayor of Tulsa hailed a long history of cooperation between tribal and local governments, and said that the court’s “recognition of tribal boundaries will not even be noticeable” to most residents.

But Muscogee citizens said they were not surprised by more alarmist responses, including a tweet by Sen. Ted Cruz, R-Texas, saying that the court “just gave away half of Oklahoma, literally. Manhattan is next.”

Muscogee citizens said they saw generations of contempt embedded in the hyperbole.

“There were a lot of scare tactics: We’re going turn the prisoners loose, give us your tax dollars, your land is our land,” said Salsman, the Muscogee press secretary. “Nothing could be further from the truth.”

The court’s decision will reshape how the criminal-justice system treats Native Americans by preventing state or local authorities from prosecuting Indigenous people who commit crimes on reservation land. Tribal or federal courts will now deal with their cases. The decision could also touch off a wave of new appeals from Indigenous people convicted by state courts.

When the Muscogee (Creek) Nation filed a brief with the Supreme Court arguing that the court honor the 19th-century treaties that created the reservation, it took pains to point out that the tribe already runs a fully functioning government. The Nation runs three hospitals, a police force and tribal court system and several casinos, which make up a major part of its $350 million budget, according to court filings. The Muscogee (Creek) attorney general pointed out that its police force regularly works with other law-enforcement agencies and spent 12 hours last winter helping a sheriff’s office track down a non-Native suspect in a double murder.

“Our pride comes from understanding our responsibilities to our fellow Creek citizens and to the community as a whole,” said Jonodev Chaudhuri, a lawyer in Washington, D.C., who is also the Nation’s ambassador. “What it means to be Creek: It means having an obligation to respect our traditions, our culture, and to learn as much as I can about our history.”

Its complicated chapters are tied up in America’s history of slavery and racism. Members of the Five Tribes brought enslaved people West with them. During the Civil War, neutral Muscogees were attacked by Confederate troops and ultimately fought both for the Union and Confederacy during the Civil War, according to the tribe.

After the war, emancipated slaves known as Creek Freedmen settled in the Greenwood area of Tulsa. It blossomed into one of the wealthiest concentration of Black businesses anywhere in America, known as “Black Wall Street,” until white residents slaughtered more than 300 Black residents and torched the area in 1921, one of America’s most notorious racist massacres.

The Muscogee lost nearly half their lands in an 1866 Reconstruction treaty, and over the following decades saw them splintered off and sold to private owners. State officials began denying that there had ever been a Creek reservation on land that became Oklahoma.

“We were assaulted daily by changes of laws, movements, politics,” said Harjo, the poet laureate. “Yet we’re still here. We’re still a viable people, one of the largest in the nation.”

This article was written by Jack Healy, a reporter for The New York Times.