On May 18, 1896, the Supreme Court upheld the constitutionality of Louisiana’s Separate Car Act, which required railroads to provide separate but equal cars to white and “colored” passengers. At the time, the case, Plessy v. Ferguson, drew little attention outside the black press. Today it is best known as the precedent that the Supreme Court overruled in Brown v. Board of Education, its 1954 decision that separate is inherently unequal in the context of segregated public schools.

Steve Luxenberg’s Separate, a history of Plessy, shows that there was virtually nothing surprising about the decision. Segregation—on trains and steamboats, in hotels, restaurants, theaters, and political associations—was a shameful but nearly ubiquitous fact of American life. For many white Americans, including those on the Supreme Court, it was also “in the nature of things,” as the court put it in Plessy. Homer Plessy’s challenge to the legality of the practice was quixotic, even after the enactment of the 13th and 14th Amendments, which ended slavery and required equal protection under the law. Nor was segregation just a Southern phenomenon; it was widely accepted, practiced, and enforced throughout the nation. The Supreme Court that upheld it in Plessy consisted of seven Northern justices and one from the South. Yet the decision was 7-1, and the only dissenter, Justice John Marshall Harlan, was also the court’s lone Southerner.

Luxenberg’s richly detailed portrait of America’s most turbulent time reveals why the case was such a long shot. The political groundwork necessary to challenge settled expectations had simply not been done yet. The country had fought a bloody civil war and formally abolished slavery, but this did not mean that most white citizens were comfortable traveling in the same circles or on the same train cars as the newly freed slaves. Even the 14th Amendment’s guarantee of equal protection was not widely thought to end segregation; indeed, the Congress that ratified the amendment had segregated seating for visitors, and no member suggested that the practice would end with the amendment’s ratification. Read from the vantage point of 2019, when racial inequality stubbornly persists, Luxenberg’s account provides a vivid reminder of how intransigent racial inequality has been and of the need to counter it through political as well as legal means.

One of the challenges Luxenberg faced in writing a book about Plessy is that there’s just not much to tell about the case itself. It was a carefully planned test case, brought by the Citizens’ Committee to Test the Constitutionality of the Separate Car Act with some collusion by the Louisville and Nashville Railroad, which did not like the extra expense of operating separate cars. As a result, the litigation affords little drama. Luxenberg builds his narrative instead around the tumultuous decades that preceded it, offering a portrait of racial politics from the abolition and secession movements of the 1830s and ’40s to the Civil War and Reconstruction.

The era that Luxenberg covers saw more convulsive change than any other in our history. Pitched political and legal battles over fugitive slaves and whether slavery would be permitted in the newly incorporated territories and states eventually escalated into all-out civil war. The Emancipation Proclamation, issued during that conflict, liberated black Americans from bondage, at least in the areas in rebel hands. In the war’s wake, the nation eventually adopted amendments abolishing slavery nationwide, guaranteeing equal protection, and protecting the right to vote. Congress also enacted a series of civil-rights laws that sought to extend the guarantee of equal treatment to the private sector. But Luxenberg’s account shows that there were hard limits to these changes; the color line was widely accepted and would not be breached for generations.

The arguments that the Supreme Court used in Plessy to justify upholding segregation, so clearly unjust and immoral today, were uncontroversial at the time. The majority in Plessy treated segregation as a given—which it was in most of the country. Today’s readers rightly blanch at the court’s contention that as long as the law required formally equal railroad cars, there was nothing demeaning about it and that if African Americans felt otherwise, that was “not by reason of anything found in the act, but solely because the colored race chooses to put that construction upon it.” But as Luxenberg shows, the court’s decision was hardly the first to rest upon such reasoning. Thirty years earlier, in a ruling by the Pennsylvania Supreme Court, the same rationale was used to uphold segregated train cars: “To assert separateness,” the court explained, “is not to declare inferiority in either…. It is simply to say that following the order of Divine Providence, human authority ought not to compel these widely separated races to intermix.”

Similarly, in 1887, the Interstate Commerce Commission, rejecting a challenge to racially segregated train cars, wrote that “public sentiment, wherever the colored population is large, sanctions and requires this separation of races,” and therefore there is no “undue prejudice or unjust preferences in recognizing and acting upon this general sentiment, provided it is done on fair and equal terms.” As is so often the case, the US Supreme Court in Plessy was not breaking ground but simply reflecting the status quo.

Notably, the case’s principal instigators, the Citizens’ Committee members, were not freed slaves but a group of les gens de couleur libres, or free people of color, from New Orleans. Of mixed race and born free, they occupied a kind of no-man’s land in America’s racial divide. As of 1860, they could own property and businesses; some owned slaves themselves. Many had fought for the Union in the Civil War. Despite enjoying certain rights, they lacked others: They could not vote, hold public office, sit on juries, or send their children to public schools.

Louis Martinet, the leader of the Citizens’ Committee, was not atypical. The son of a European man who had bought a slave’s freedom in order to marry her, he had considerable education, ran a newspaper, was politically active, and advocated for equal rights, yet his own political and civil rights were still curtailed in Jim Crow Louisiana. To challenge this, he and the Citizens’ Committee recruited Plessy, a light-skinned shoemaker, to serve as the plaintiff in the case. Plessy’s family tree “featured every color of the New Orleans spectrum, but no enslaved member since his great-grandmother had gained her freedom in 1779.” As Luxenberg writes, such men were “free, but fenced in.” With Plessy’s case, they sought to bring down the fences.

The case, however, was destined to fail. Indeed, it was so hopeless that Frederick Douglass declined to support it. He and others recognized that the court was not ready to eradicate a nationwide system of segregation by judicial decree; a considerable amount of political mobilization would be needed to effect such a profound transformation of the way things were.

Martinet himself harbored few illusions about winning the case. He explained what spurred him to file it in existential rather than strategic terms. In a letter to Albion Tourgée, the lead attorney for Plessy, Martinet wrote, “What have I to gain in fighting this battle? Like you, I have asked myself this question a thousand times. I want no political influence, no prestige, no office. Why do I do this? Like you, I believe I do it because I am built this way.”

As the case approached the Supreme Court, Martinet’s uncertainty grew, and he and Tourgée began to get cold feet. They discussed delaying its resolution because they believed that only the “pressure of a mass movement” could lead the court to rule in Plessy’s favor. But this recognition came far too late, and they could not muster such mass support overnight. They did start a national newspaper to advocate on the issue while the case was pending before the court, but there is only so much a newspaper can do. In the end, it took the better part of a century to produce the political pressure that proved necessary to end Jim Crow segregation. Martinet, Tourgée, and Plessy were way ahead of their time.

Luxenberg tells his story through the lens of some of the key individuals involved: not just Martinet and Tourgée but also Justice Henry Billings Brown, who wrote the court’s majority opinion, and Harlan, the lone dissenter. Martinet and Tourgée are heroic figures, and their struggle against segregation helps drive the book. But the most compelling character is Harlan, whose dissent becomes all the more surprising when one learns his life story.

The son of James Harlan, Kentucky’s attorney general (who named his son after the nation’s fourth chief justice, John Marshall), John Harlan grew up in a privileged family that owned 14 slaves. In his early 20s, before the war, he joined the nativist American Party, more popularly known as the Know Nothings, whose members pledged never to vote for a foreign-born or Roman Catholic candidate for office. At the time, he viewed slavery as a matter for each state to decide for itself, and he supported the Fugitive Slave Act. During the war, he fought in the Union Army, but he did so expressly to preserve the union, not to end slavery.

Even after the Civil War, Harlan opposed the 1866 Civil Rights Act, which authorized black citizens to testify in court, seeing it as an improper federal incursion on state authority. He opposed the 1875 Civil Rights Act, which forbade racial discrimination in hotels, restaurants, and other public accommodations, on the same states’-rights ground.

But Harlan also opposed secession, and after the Civil War he prosecuted Ku Klux Klan members for the federal government. He befriended Frederick Douglass and, when challenged on this by an opponent during a Kentucky gubernatorial campaign, replied, “I not only do not apologize for what I did, but frankly say that I would rather eat dinner any day by the side of Douglass than to eat with the fellow across the way who sought to entrap me with a question that has nothing to do with this contest.” Most important, as a Supreme Court justice, Harlan reversed his earlier states’-rights views and staked out a lonely position arguing forcefully for an expansive understanding of the 13th and 14th Amendments.

In the Civil Rights Cases, the court ruled in 1883 that while the amendments ended slavery and required states to provide equal protection, they did not authorize Congress to prohibit private discrimination—the view that Harlan himself had taken when the acts were being considered. As a justice, however, he argued in a solo dissent that these amendments were intended to extend to the newly freed slaves all the fundamental rights enjoyed by whites and that they authorized Congress to prohibit private discrimination to that end. He sounded a similar note in Plessy, arguing that the 14th Amendment does not countenance segregation, that separate is inherently unequal, and that all distinctions based on color are constitutionally suspect.

Of course, Harlan’s views ultimately prevailed. But Separate reminds us how deeply rooted segregation was. There was no way that Martinet, Tourgée, Plessy, and Harlan could uproot it on their own. It would take the concerted and brave work of tens of thousands of Americans over many decades to build a movement that brought formal segregation to an end.

Separate vividly tells the story of how far our country had to go to repudiate its commitments to a racial double standard. A visit to any prison or inner-city public school today reveals how far we still have to go.