In the iconic geography of the civil rights movement, the South understandably looms large. Selma. Birmingham. Greensboro.

Washington? Not so much.

But as the nation reflects on the struggle for racial equality this Martin Luther King Jr. Day, the capital’s mostly forgotten history of integration is worth remembering. Washington was a key civil rights battleground, especially in the years before the Supreme Court’s landmark 1954 school desegregation decision in Brown v. Board of Education. In fact, in 1953, a Supreme Court decision that desegregated Washington restaurants paved the way for Brown and nationwide school integration a year later.

The 1953 ruling, District of Columbia v. John R. Thompson Co., Inc. , is little-known now, but it was groundbreaking. It came at a moment when the court had failed to coalesce internally over how to resolve Brown and four companion cases, including one that challenged Washington’s segregated schools.

Thompson was handed down four months after President Dwight D. Eisenhower vowed, in his first State of the Union address, to end segregation in the capital. It was not brought to the court by one of the lawyers most associated with Brown and the civil rights movement: Thurgood Marshall. Instead, it came at the instigation of an octogenarian activist and charter member of the NAACP named Mary Church Terrell. With Thompson, a standalone challenge to Washington’s Jim Crow restaurants, the court expressed a consensus it couldn’t yet articulate in Brown and the other school segregation cases, which teemed with the complexities of directing the era’s black and white children to sit side by side.

Terrell’s legal battle began Jan. 27, 1950, when Thompson’s Restaurant, a cafeteria at 725 14th St. NW, a few blocks from the White House, refused to serve her and two African American colleagues because they were “colored.” Terrell had lived in Washington for 60 years. She knew segregation. The District was then 35 percent black, but schools, movie theaters, department stores and other businesses were strictly separated by race. Most downtown restaurants denied service to blacks; some relegated them to a counter, where they had to stand. In fact, in a 1948 report by the National Committee on Segregation in the Nation’s Capital, a traveler from India said this: “I would rather be an Untouchable in the Hindu caste system than a Negro in Washington.”

Even the Supreme Court’s first African American law clerk, William T. Coleman Jr., a Harvard Law School graduate whose one-year tenure with Justice Felix Frankfurter ended in 1949, could not join colleagues for lunch at the Mayflower Hotel. Instead, he and a fellow clerk went to Union Station, where blacks and whites could eat together, as they could in federal government cafeterias — which had quietly integrated during President Franklin D. Roosevelt’s administration. That move didn’t bind private business in the District, even though the city didn’t govern itself independently.

Still, after she was refused service, Terrell went to local prosecutors, seeking to enforce Reconstruction-era ordinances that banned Washington restaurants from discriminating. The laws, still on the books almost a century later, had long been ignored, prompting The Washington Post to ruminate, in an editorial on Feb. 24, 1950, about the vanished “sense of common humanity” that had spurred their enactment. “But it is a sense that needs to be regained,” the editors added. Terrell pursued her challenge without help from the NAACP, working instead with the progressive lawyers, activists and communists with whom she had aligned. A trial judge initially dismissed the charges against the restaurant, finding that the old anti-discrimination statutes were no longer valid. The case would work its way through the courts for the next three years.

In the meantime, Terrell kept up her organizing for civil rights, working with local activists to boycott the downtown department store Hecht’s, which segregated its lunch counter. In January 1952, after eight months, the store relented.

The District had special relevance to the doctrine of legalized segregation. In Plessy v. Ferguson , the Supreme Court’s 1896 decision upholding segregated railway cars in Louisiana, the justices referred, in part, to the fact that Congress required segregated schools in D.C. The court’s reference was a nonbinding comment, but it bolstered the rationale of the case. And the rationale went, in part, like this: If Congress, which had jurisdiction over the District, could require segregated schools in the capital, surely Louisiana could segregate its railway passengers.

But Thompson relied on local anti-discrimination laws and did not directly confront Plessy. That made the case a vehicle for the court to deal with segregation in private businesses. Stalled amid the complexities of school integration, the court pivoted to Washington and to the Jim Crow restaurants at its doorstep. In April 1953, urged on by the Justice Department, the justices agreed to hear Terrell’s case. The NAACP, which had mostly been focusing on school desegregation lawsuits, did try to participate once Thompson reached the high court. In a written filing seeking permission to submit a “friend of the court” brief, Marshall and his colleagues argued that Thompson was a case of nationwide importance, not a mere local dispute — precisely because it challenged Jim Crow in the nation’s capital, the symbolic home of American democracy. But the court denied their request to file a brief, without explaining why.

On June 8, 1953, the court ruled unanimously in favor of Terrell, finding that the decades-old provisions banning racial discrimination in public accommodations in the District remained “presently enforceable.” That same day, the court scheduled Brown and its companion cases for another round of oral argument in the fall. The justices had been winding down the term, taking care of unfinished business before the summer recess. But Frankfurter took pains to confirm, in a letter to Chief Justice Fred M. Vinson dated June 8, that the court would hand down the Brown order with Thompson.

After Thompson, the capital saw no bloodshed or rioting, no racial unrest. When the local black newspaper, the Afro-American, wrote about Terrell’s victory, its headline read simply: “Eat Anywhere.” Within days, Terrell returned to Thompson’s, which finally served her. “It’s like another Emancipation,” said the Rev. Graham G. Lacey, a local minister who was there to witness the event.

Thompson did not overrule Plessy. But it did send a signal: The justices had all but rejected the culture of Jim Crow and race-based exclusion, of line-drawing and whites-only dining rooms. Washington restaurants, once resistant, yielded to integration. So did movie theaters, which Terrell targeted after her win in the Supreme Court.

Less than a year later, on May 17, 1954, the court unveiled its unanimous Brown decision. In a separate opinion, Bolling v. Sharpe, the court invalidated D.C.’s segregated schools. With simple, declarative language, the justices did expressly what they had done symbolically in Thompson: They repudiated Plessy and “separate but equal.” After Brown, amid white supremacist backlash, the battle shifted to the South. The District had played its part.

Twitter: @joan_quigley

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