But Robert and John shared more than a last name. They had grown up in the same house. Each had watched the other rise to national prominence. They had come to express similar political sentiments.

There was also one difference: One of them, Robert, was born into slavery. But their relationship remained close enough that they strategized together in the days surrounding the 1876 Republican convention, which nominated the man who had just become president at the time the letter was sent, Rutherford B. Hayes. And some newspapers had reported as fact what had long been rumored: They had the same father.

Whether that was true or not, Robert, who was 16 years older, knew that John’s late father had dreamed of John going to the Supreme Court since giving the newborn baby the name of his own legal hero, Chief Justice John Marshall.

Forty-four years later, John was in contention for the court seat being vacated by one of Abe Lincoln’s old friends, David Davis, and Robert was taking on the self-appointed role of adviser and protector.

Hayes, who had prevailed in a disputed election by promising concessions to Southern whites, wanted to pick a southerner for the court seat. But that appointee would have to run a gauntlet: confirmation by a deeply suspicious Senate Judiciary Committee headed by a Vermont Republican who was wary of Southern backsliding on civil rights.

So any nominee had to be both Southern and fully satisfactory to Northern progressives.

At this perilous moment, John Harlan agreed to take on one of the most politically thankless tasks of the era: serving as one of Hayes’ representatives to assess a violent uprising in Louisiana, where disruption in state elections had yielded rival governments. The situation was so fraught that the Republican governor was a virtual prisoner in his makeshift statehouse. His allies cited massive violence that had kept Black voters from the polls. Democrats, however, decried the federal mandates preventing unrepentant Confederates from exercising their franchise, restrictions that were enforced by U.S. troops, still mustered in New Orleans 12 years after the end of the Civil War.

Almost everyone sensed that Hayes was on the verge of removing the troops, part of the unwritten bargain that had enabled him to assume the presidency. And many people believed that Hayes’ Louisiana Commission, which John Harlan had just loyally pledged to join, was a sham orchestrated to produce the very outcome that had already been promised: restoration of power to racist Democrats.

In Robert’s eyes, focused on the Black community and its Northern allies, no good could come of this commission. John was sacrificing his career to Hayes’ convenience. Radical Republicans would never confirm a Supreme Court justice who could be blamed for surrendering to a mob of ex-Confederates. In political terms, John was wading into a swamp, and Robert knew it. So he did something surprising for a person born enslaved, even one reported to be in the family bloodline: He invoked their common upbringing, conjuring the memory of the family patriarch and speaking in the kind of code that only family members use.

Do-do-take-care.

John did take care. The Louisiana Commission proved to be just as much of a powerless dead end as Robert had envisioned, and Hayes removed the troops. But John managed to extricate himself from the mess by plausibly claiming that the Republican government had collapsed on its accord. His service earned him Hayes’ approval, and by October 10 Robert was writing from Washington that he had conferred with many people who had touted John’s Supreme Court credentials to Hayes and that they “had no doubt that you will be appointed.”

The rest is history. John Marshall Harlan went on to have a miraculous career on the bench, earning the sobriquet “The Great Dissenter” for his uncanny prescience. He took forward-looking stances that not only envisioned the legal structure of the 20^th century but helped to shape it. Most importantly, he stood alone in fighting back against his colleagues in the cases that destroyed African-American hopes for generations: The Civil Rights Cases of 1883, which deprived Black people of access to railroads, inns and theaters; Plessy v. Ferguson, which endorsed the legal underpinnings of segregation; and the punishing Berea v. Kentucky, which gave the constitutional stamp of approval to a law banning interracial education even in private schools where people of all races wanted it. At this utterly dark moment in American law, John Marshall Harlan was a solitary beacon.

Robert Harlan maintained a semblance of political clout in Ohio, even managing to get elected to the Buckeye State legislature. But it was a time of rapidly declining fortunes for African-Americans. Robert got caught in the undertow. Even a person of his stunning resourcefulness, who had bounded from slavery to fame as a horseracing pioneer to wealth in the Gold Rush to influence as a post-Civil War political leader, had nowhere to turn in a system that drew ever-tightening walls around the Black community. The Black-owned businesses that Robert had bankrolled as early as the 1850s couldn’t survive without white customers; even the Republican Party, which had first embraced and then tolerated him in the belief that he could deliver African-American votes, lost its incentive after voting rights came under siege.

The man The New York World said wielded “influence over his race second only to Fred Douglass” became lost to history.

Now, as more and more newspapers from the 19^th century become digitized—including the African American papers and racing-industry journals that tracked Robert like a celebrity—it’s easier to tell the story of his amazing life. It’s a global adventure tale for the ages, spanning oceans and covering some of the most important events in American history. But it comes wrapped in a mystery. The restoration of old news accounts answers the questions of who-what-where, but the whys remain unexplained.

Having set out to write a book about John Marshall Harlan—a deeply inspiring figure who is unknown to most Americans—I had the strange experience of watching that story converge with another, equally inspiring one. There’s a swashbuckling, ready-for-the-movies hero in the book, and it’s not John Marshall Harlan. It takes nothing away from Justice Harlan to say that Robert pushed past more boundaries, just as it doesn’t diminish Robert to say that part of his legacy may well be embedded in the Supreme Court dissents penned by the man that he, Robert, helped elevate to the bench.

But any attempt to sketch the contours of that relationship requires delving into the unique and painful position of the biracial and multi-racial elites that dominated African-American politics in the 19^th century. Many of those leaders had real or presumed blood ties to the families under whose ownership they were enslaved. These figures, privileged among Black people but shunned and degraded by many whites, were products of the ultimate in dysfunctional backgrounds. For them, the most basic relationships were twisted and tarnished by slavery. Some broke away entirely. Some managed, through what must have been a disciplined effort, to factor out the distorting effects of slavery, and forged functional relationships with those beside whom they had grown up.

Harvard law professor Annette Gordon-Reed, in her study of the family created by Thomas Jefferson and the enslaved Sally Hemings, suggested that such units were simply too hidden and warped by slavery to be fully understood by history, and can only be assessed—like a lawyer preparing a case—by examining the motivations of the various parties and parsing the preponderance of the evidence.

That is certainly true in the case of the Harlans, as well. But what emerged from the parsing and assessing was something unexpected. It was not a story about roots or bloodlines. Nor was it fundamentally about exploitation, the pain of inequality, or even the way slavery perverted basic emotions; it was about how, despite all of those things, a feeling grew up between Robert and John Harlan that was authentic and organically human: respect.

Robert really believed in John—in his wisdom and fitness for the Supreme Court—when other people had reasons to doubt him. And despite the strange imbalances in their backgrounds and the pressures of a society eager to demean African Americans, John accepted Robert’s friendship and help in a spirit of equality.

The theme of the book came into focus: It is, at bottom, a story about the vital importance of respect and understanding.

Robert’s upbringing was recounted on many occasions in the journals of his time, though some details differ. Most agree, however, that he was born on a plantation in Mecklenburg County, Virginia, near where James Harlan of Kentucky, who was 16 at the time, had relatives.

When Robert was eight, he and his mother journeyed westward through about 460 miles of mostly wilderness in search of his father. They alighted at Harlan’s Station, a tiny hamlet founded James’ father and uncle. By some accounts, Robert and his mother discovered that his father was dead; others claim James was the father. Either way, James, just 24 and recently married, took ownership of the boy, while Robert’s mother was sold down the Mississippi River to Louisiana. How these transactions came about, and by whom, was never explained, except that at least one account indicates that Robert’s mother wrote to James from Louisiana—another unusual occurrence, which suggests she was both literate and trusting of James.

In all the accounts, Robert describes himself as having been raised by James, with scant mention of James’ wife, Eliza, who bore him nine children. John was the sixth, and fifth son. Like the others of James and Eliza’s sons, John was committed to a regimen of study designed to make him a lawyer like his father. James wanted to educate Robert, too, but in an oft-told story the schools wouldn’t take him because of his race, so he went through life declaring that he had “half a day’s schooling.” Liberated from classes, he roamed the state as a young man and developed a second-to-none expertise in horseracing, Kentucky’s nascent sport in which free and enslaved African-Americans played leading roles as jockeys and trainers.

With his dashing looks, and the fearlessness that came from organizing races and collecting bets in places that were a generation removed from the frontier, Robert must have made a powerful impression on John as a child. There was, as well, that unspoken connection between John’s beloved father and Robert.

For Robert, those years were the start of a lifetime of sussing out opportunities in places and situations where Black people might, by chance, be given an equal shot. These included opening a store in Lexington, Kentucky, before Black laws and mob violence drove him out; a torturous adventure across Panama and up the Pacific Ocean to Gold Rush-era San Francisco, reasoning that racism had yet to take root in the lawless West; investments in Black-owned photography studios in Cincinnati, with the understanding that there were no barriers to new technology; the founding of Cincinnati’s first school for Black children, having engineered the financial backing of the city’s richest citizen; investment in Cincinnati’s leading Black hotel, which doubled as a stop on the Underground Railroad; highly publicized trips across the Atlantic Ocean to Europe, bringing American horses to challenge British supremacy in the Sport of Kings.

Robert spent about a decade, including the Civil War years, in Europe, where he was treated like a celebrity in the horseracing world and seemed to encounter little prejudice on account of his race. Returning to Cincinnati, he assumed a leadership role in the Black community, whose rights finally seemed to be protected by the Reconstruction-era amendments to the Constitution. With all the places he had gone and things he had accomplished—and a personality that combined the suavity of a gambler and showman with the erudition of a man of the world—Robert finally seemed to have reached the pinnacle of success. And he wanted to inspire others of his race.

Celebrating the passage of the Fifteenth Amendment to Congress in 1870, which granted Black people the right to vote, Robert spoke before an audience of Black and white people at a Cincinnati jubilee and offered his own prophecy, his creed: “Knowledge is power; and those who know the most, and not those who have the most, will govern this country. Let us combine and associate and organize for this end. In the pulpit, in the press, in the street, everywhere let our theme be education, education; until there cannot be found anywhere a child of us that is not at the school. With this endeavor carried out, who can measure the progress that may be made in a single generation by a poor, despised, and enslaved race? Then, indeed, would vanish prejudice; then would the noble martyrs of our cause not have died in vain, and human slavery would evermore be an impossibility.”

Robert believed those words. He imagined his son, Robert James Harlan—whom he named after James Harlan—living on equal terms with the scions of privileged white families. Robert Jr. attended Cincinnati’s largely white Woodward High, where he was classmates with William Howard Taft, and went on to college and law school.

Robert raised his son almost on his own, and also served as a backstop for the extended Harlan family. When John’s older sister, Elizabeth, got married, Robert presented her with the most extravagant of presents, a handmade piano. Later, when one of John’s brothers, James Jr., became destitute and an alcoholic, Robert stepped in with multiple levels of support. “Bob Harlan has for two years been unusually kind to me, not, however, putting me under any obligation,” James Jr. reported to John.

In John’s case, Robert’s gift was political help—and he was ideally positioned to help John gain credibility with Republicans who doubted his conversion to their party after the Civil War. In the first dozen years after the surrender of the Confederacy, African-Americans were an important Republican constituency, and Northern Republicans were wary of Southern efforts to push Black people back into positions of subjugation.

In that atmosphere John became entangled in a scandal that jeopardized his national aspirations. It was 1871, and John was in the midst of a futile campaign for governor of Kentucky under the Republican banner. He loyally and steadfastly defended the national party even though it was held in contempt by much of the Bluegrass State. Still, many northerners could only remember the fact that he was from a slave-owning family and had criticized abolitionists before the war. Then came an incident in which John’s drunken cousin from his mother’s side of the family shot a prominent Black federal official in Washington. Though the motive may have been personal—the Black official was advising a person who wanted to sue the cousin over the sale of a faulty stove—many in the Black community saw the case in starkly racial terms.

At the time, judicial matters in Washington were handled by the federal government, and it happened that John’s good friend from Kentucky, Benjamin Bristow, was President Ulysses Grant’s solicitor general. When the lawyer for John’s cousin let it be known that he had appealed to John for help, many Black leaders smelled a rat. On the hustings in Kentucky, John seemed unaware of just how harmful to his future ambitions those rumors could be.

Robert did, and rushed to the capital from his own home in Cincinnati to quell the damage. The victim, Orindatus S. B. Wall, was a Civil War veteran and fellow member of the African-American elite. Wall’s brother-in-law was John Mercer Langston, the founding dean of Howard Law School. Robert was friends with both of them, along with Amanda Wall, who believed her husband had been shot “because he was a colored man and held an office,” as Robert frankly reported to John.

Robert suggested the whole situation was more serious than John believed, noting that Langston—who had the clout to raise a ruckus—believed that “you had written to the president and … authorized other parties to draw on you for large amounts of money for the purpose of clearing” his cousin James Davenport.

Robert proposed a different approach. He defended John to Black leaders in Washington as guilty of nothing more than attempting to spare his family from embarrassment. But, Robert assured them, John had no illusions about the wrongness of his cousin’s actions. Robert, too, had known Davenport “almost from childhood” and described him as having been damaged by the war, in which he fought on the Union side. Robert then brokered a deal: If Davenport were to go free, the Harlan family would guarantee that the troubled man would never set foot in the District of Columbia again. Thus, he would plead guilty to assault with an intent to kill, but President Grant would pardon him on the grounds that he wasn’t in possession of his faculties. The Walls and Langstons kept quiet, and the Harlans satisfied their end of the bargain.

This delicate negotiation marked a period of close collaboration between John and Robert, who, five years later, would jointly organize support for Bristow’s unsuccessful presidential run. Then, at the 1876 Republican convention in Robert’s hometown of Cincinnati, John played a key role in shifting Bristow’s backers to Hayes, the former Ohio governor who had worked with Robert in creating the first all-Black battalion in the state National Guard.

And when Hayes became president, Robert endeavored to see that John was rewarded with the prize he had always wanted: the Supreme Court.

Despite their shared biography, the relationship between John and Robert Harlan fell into a deep pit of silence. Many famous people—Douglass, Taft and Hayes among them—knew both men well and yet seemed wary of acknowledging a connection, adhering to the “don’t ask, don’t tell” social etiquette of the era.

What, then, can we make of the relationship by applying the analysis of motives suggested by Gordon-Reed? Could Robert have reached out to John to underscore his membership in a prominent family? It’s unlikely, since such links were usually unspoken and considered embarrassing to all concerned. Later in Robert’s life, a mischievous journalist for The Louisville Courier-Journal described Robert as “a well-proportioned mulatto … built on the same heroic molds as Associate Justice Harlan of the United States Supreme Court, and only differs in facial appearance by being more sallow and wearing a jet-black mustache, while the eminent jurist is a clean-shaved, decided type of blond.” But even if Robert was proud to have been raised by James Harlan, that wouldn’t account for his actual kindnesses to the family; James had died in 1863 and Robert didn’t need to stay in touch with anyone in the family to vindicate his relationship with James.

Perhaps Robert’s kindnesses to the Harlans were motivated, even in some small part, by a very human desire to serve notice that he had attained wealth and power against tremendous odds. That might have been true of the piano gifted to Lizzie or even the offer of a leg up to James Jr., but not his lobbying for John. Robert’s political capital depended on his credibility with people like the Walls and Langstons—and, for that matter, the Grants and Hayeses—and he wouldn’t have wasted it just to show off his clout. Plainly, he exerted himself on John’s behalf because he believed in John as a leader and a jurist, and felt he understood him better than his critics did.

That realization—that Robert’s embrace of John was probably deeply felt, and that Robert, in fact, conceived of himself as a leader and protector of the Harlan clan—casts his other actions in a more tender light. Given his special relationship with James, would he not have tried to assume more of an advice-giving paternal role after James’ death? (“do-do-take-care”) The simplest explanation for the gift to Lizzie was that he wanted to make her happy on her wedding. His concern for James Jr.’s wellbeing also bespeaks a familial feeling. Most importantly, Robert knew better than anyone that their father’s great wish was to see John on the Supreme Court.

Sporadic letters, only some of which have been passed down posterity, can only reveal so much. They don’t specify the extent of Robert’s exertions on John’s behalf when the Supreme Court nomination hung in the balance. But the totality of the evidence suggests that Robert’s role was important and may have helped tip the scale in John’s favor.

Less is known of Robert and John’s later relationship. Any correspondence in the years after John joined the Supreme Court is lost. (Robert’s letters were never collected, and John’s are incomplete.) It’s quite possible that they didn’t write each other for the simple reason that Robert made regular trips to Washington to see his son and could visit John in person. It’s also possible there was some sort of breach between them. If so, though, it would be surprising that John’s wife Malvina would choose to mention Robert in a positive light in her short autobiographical narrative written after John’s death. She told the story of the piano he gave to Lizzie and dubbed Robert a “quasi-family member.” That may sound like thin gruel to current sensibilities, or even a bit of a snub, but when written in 1915 it was an almost daring acknowledgment of a close tie to the person long believed to have been her husband’s half-brother.

Later generations of Harlans on both sides also felt themselves to be related. But when a law professor in 2001 asked them to take a DNA test, it came back negative, suggesting a blood link was unlikely. The test wouldn’t account for any breaks in the DNA links on either side over as many as five generations. But Eve Dillingham, John’s great-granddaughter, expressed disappointment. “Regardless, there was a great bond between the two, she said, and ‘whether it was a blood bond or not doesn’t matter so much,’” the Associated Press reported.

The question of whether Robert and John were biological siblings matters less to history. After all, they did not have the benefit of DNA tests. The belief that they were related may have affected their relationship, but so too would other factors, like having shared a name, a home and love for the same father figure. They also knew each other and watched each other’s careers.

Their relationship takes on added significance, however, in light of what happened in Black-white relations over the span of their lives. America moved from the abolition crisis to civil war to a Reconstruction era marked by efforts to promote legal equality to a total, systemic abandonment of that effort. The doors to American society were not only shut to African Americans, but locked, bolted and barricaded with heavy furnishings.

The Supreme Court bore much of the responsibility for this, and John Marshall Harlan provided the only voice in resistance. And it was a powerful one. Starting with the Civil Rights Cases of 1883, he issued dissent after dissent in cases that removed civil rights, voting rights and access to integrated education. In time, those dissents became grist for the 20^th civil rights movement, inspiring Thurgood Marshall, Constance Baker Motley and other Black legal pioneers. They also represented, to African-Americans, the only hope that white people might ever be able to view the law through their eyes.

Since John Marshall Harlan came from a slave-owning background, his position as a great defender of African Americans has been cast as an irony, a mystery, an enigma. Certainly, it had many roots, including the lessons in watching his home state torn apart by the Civil War, which he blamed on the cancer of inequality. But his dissenting opinions weren’t just assertions of principle; they were replete with references to the actual wrongs done to Black people.

Reading the cases today, one realizes that they weren’t the kind of thorny legal matters on which reasonable people might disagree. They were abominations that violated the spirit, meaning, intention and plain language of the Constitution. The words of the majority opinions were not only venal but cloddish and ignorant. “We consider the underlying fallacy of the plaintiff’s argument to consist in the assumption that the enforced separation of the two races stamps the colored race with a badge of inferiority,” wrote Justice Henry Billings Brown in a breezy passage in Plessy v. Ferguson. “If this be so, it is not by reason of anything found in the act, but solely because the colored race chooses to put that construction on it.” This, in response to a law that was deliberately engineered to force Black people into a separate carriage!

The court’s majority—almost all wealthy northerners who had little contact with African Americans—sought refuge in theories of Black inferiority. Justice Harlan, of course, did not. He spoke regularly to Black audiences at Washington’s Metropolitan AME Church, ordered reviews of racist criminal procedures in Tennessee, held public officials accountable for lynchings, approved a petition by a Black lawyer for probably the first time in Supreme Court history and, on a final nostalgic visit to his segregated home state, embarrassed his hosts by insisting on meeting with a group of Black attorneys.

When Frederick Douglass—once the toast of white abolitionists—died, America’s white leadership turned its back. Only Harlan and Ohio Sen. John Sherman, brother of the Civil War general, deigned to attend his funeral. When, a decade and a half later, Harlan passed away, Black churches staged memorial services in every corner of the country. His dissents were read aloud. “Now that he is gone we cannot help but tremble, and fear that no one after him may dissent against decisions against our race,” editorialized The Washington Bee.

Until very recently, little has been known about John Marshall Harlan’s relationship with Robert Harlan, and even less has been remembered about Robert himself. It’s long past time to open the door on a relationship that, in transcending both the evils and after-effects of slavery, attests to the better nature of the human spirit. And it’s time to recognize that Robert Harlan deserves a place among the important figures of his time.

Here was a man born into slavery who not only achieved material riches but helped develop the sport of horseracing, founded Black-owned businesses, built a school, started the first all-Black National Guard unit in his state, fought for civil rights and played a central role in crafting a national Black political agenda. Along the way, he endured relentless discrimination. White vigilantes helped drive him out of Lexington, Kentucky. He was attacked by the Ku Klux Klan. As a federal postal agent, he had to travel with armed guards. Racial insults were hurled at him on the floor of the Ohio Legislature. But he kept his optimistic character intact. Hungry for worldly experience, he attended the legendary Heenan-Sayers bare-knuckle prize fight in England, gambled in Cuba with the Mexican General Antonio López de Santa Anna and debated the fate of the French Republic with Senator Charles Sumner, a conversation that one account suggested may have been conducted in French.

He was a stunning example of the triumph of human will over some of the greatest social and legal obstacles ever surmounted. No one who knew him could buy into those noxious doctrines that served as a pretext for the rankest discrimination.

John Marshall Harlan, alone among the leading jurists of his day, did not.