Harriet Tubman, who had been a slave herself, led slaves to their freedom through the Underground Railroad. (World History Archive / Alamy Stock Photo)

One day in 1965, an African American couple knocked on John Creighton’s door in Cambridge, Md., for directions to Harriet Tubman’s birthplace. As time passed, others followed. Creighton, then in his mid-20s, was caretaker of the Dorchester County Historical Society’s grounds — his family lived in the society’s quarters. After a historical marker about Tubman was placed in 1967 in the area, the interruptions increased. Some who knocked on his door told him about Tubman’s role in American history; others asked him questions about her he could not answer.

It was the high school students he taught in the early 1970s who finally pushed Creighton to begin investigating. His lesson about Tubman, he wrote years later, “elicited an avalanche of further questions about local details.” He got a copy of Earl Conrad’s 1943 biography and shared it with his students. They kept asking questions. One girl was highly skeptical of one escape story, causing Creighton to do research with his students.

Tubman, the most renowned agent on the Underground Railroad, had long been shrouded in myth and folklore. Barely 5 feet tall, an illiterate field hand who suffered from severe seizures, she escaped slavery on Maryland’s Eastern Shore, then returned to shepherd at least 70 enslaved blacks to the North.

Creighton and his students examined various books and oral histories about Tubman. They found mistakes and kept going.

John Creighton never stopped.

Some historians would eventually credit him as the one most responsible for what we know about Tubman’s first four decades. He devoted nearly 40 years to investigating her life and African American communities in Dorchester and Caroline counties, where her daring ventures originated. He studied not just Tubman but the slaves she rescued and the web of people in the Underground Railroad who helped her. Yet he himself remained largely unknown.

John and I had become close friends in the early 1970s. A year ago he died of cancer, at 73, still pursuing Tubman’s trail with his longtime research partner and companion, Pat Lewis. In his obsessive search, John had let his marriage fall apart and given up any shot at material success. At one point he was almost penniless and slept in a garage. Despite our friendship, what drove him to pursue Tubman’s story for half his life and sacrifice so much was a mystery to me.

For years those of us who knew John awaited his own biography of Tubman, but it never came. He never published a word about her. I wanted to unravel that mystery.

John Creighton as a young man on the Eastern Shore of Maryland, with Cambridge Creek in the background. (Photo courtesy of Suzanne Trice)

John grew up in Wilmington, Del., but spent the summers on the Eastern Shore, where both sides of his family had lived for generations. After earning a bachelor’s degree in economics at Swarthmore College and an MBA at the University of Pittsburgh, he became a widely published poet, writing mostly about the Eastern Shore.

He married his high school sweetheart, Sandra Salzenberg, in 1963, and they had three children. When Swarthmore offered him the job of assistant to the president in 1974, they moved nearby to Chester, Pa. Over time he grew unhappy, complaining that he was just a glorified secretary.

His son Daniel recalled the day, in 1976, when his father came home and announced that he had quit. “Well, that’s great, John,” Sandy said, according to Daniel. “We’ve got a mortgage to pay and three kids. What’s the plan?”

John had no plan but to live off his poetry and other writing. He retreated to his office in the attic. “We didn’t know what he was doing up there on the third floor surrounded by 3-by-5 cards and a 20-watt light bulb,” Daniel said. He now knows that his father had resumed his research on Tubman.

A file cabinet in Creighton’s home contains just some of his research on Harriet Tubman and other related subjects. (Photo courtesy of Pat Lewis)

Equipped only with his index cards and an extraordinary memory, John learned all he could about Tubman, the more than a dozen escapes she led and the people who abetted her journeys on the Underground Railroad. He visited libraries and courthouses from Maryland to New York and pored over land and chattel records, arrest records, census data, diaries, journals and 19th-century newspapers.

William Jarmon, former head of the Dorchester County Historical Society, told me what set John apart from other Underground Railroad historians was his emphasis on African American oral history, his quest to learn family lore and better understand the era of slavery.

“His hands were in the soil,” Jarmon said. “He went as deep as he possibly could.”

In the end, said J.O.K. Walsh, who has long headed the Caroline County Historical Society, John had put “a factual foundation” under Tubman’s story. Even Tubman’s birth was undocumented until John discovered a $2 payment to the midwife who apparently delivered Tubman in Peters Neck, now widely accepted as a record of her birth and birthplace.

He traced family genealogies — black and white. By the end of his life, his collection of notecards, which became both his trademark and the subject of jokes, was estimated at more than 50,000.

Around 1978 John submitted an article to what then was called the Journal of Negro History about how he had determined who Tubman’s parents and siblings were. It was never published. Years later, when he was working with Kate Clifford Larson, who would write an acclaimed biography of Tubman, he told her what happened.

“They sent it back to him and asked him to make corrections and he refused,” Larson told me in an email. “Then he railed against them as not seeking the truth.”

John made one more stab in the early 1990s, when he wrote an article aimed at the Wall Street Journal about his pursuit of Tubman’s story. It wasn’t published, either.

Was that enough to keep him from ever trying again?

After John quit Swarthmore, his mother-in-law supported the family until Sandy got full-time work for an oil company. Daniel told me John “got furious with [Sandy] for pursuing the corporate dream, being a lemming and trying to make more money like everyone else.”

Sandy eventually moved out with the kids, and she and John divorced. He did some substitute teaching and cashed in stock, a gift from his father. When their house sold years later, John camped out in an acquaintance’s garage for two months.

He moved to the Eastern Shore and over the next few years lived in nearly a dozen places while pursuing Tubman research. He also started mentoring other Tubman historians and volunteered at the Harriet Tubman Association (now Organization) in Cambridge, but he never held another job. His family helped him financially.

By the 1990s John’s reputation had spread, and writers, filmmakers, scholars and artists from all over the country sought him out. He gave them private tours, without charge, through the largely unchanged Eastern Shore forests and marshes Tubman had trod. Among those who showed up were novelists James McBride and Betty DeRamus. He gave free tours to people who were simply interested, too.

“He was enormously generous,” Walsh said. John started a discussion group at which he and Pat Lewis shared their knowledge. They circulated their research in handouts that ran 20 to 40 single-spaced pages.

John Creighton with his longtime research colleague Pat Lewis. (Photo courtesy of the Harriet Tubman Museum and Educational Center)

Larson published her biography of Tubman, “Bound for the Promised Land,” in 2004. John had told me that he had worked with her when it was a dissertation but that they’d eventually had a falling out.

When John initially learned Larson was writing a book, he was taken aback, according to both Ann Phillips, current director of the Dorchester County Historical Society, and Lewis. “It was almost like [to John] she had a character flaw by wanting to profit off research on Harriet Tubman,” Phillips said.

But Lewis said that John was happy about the book’s publication and that he and Larson talked on the phone for several years afterward.

John and Larson would be involved in another project as well. In March, Maryland will open a state park commemorating Tubman and the Underground Railroad. A 125-mile byway through Dorchester and Caroline counties already enables people to take self-guided driving tours and hear the stories of Tubman and others who fled slavery.

John was active in planning the state park and byway, and was part of working groups that guided their development, said Marci Ross, a state tourism official.

“The whole reason the state has an Underground Railroad Byway,” Ross said, “was that John felt so passionately about having some sort of driving tour.”

A number of historians were paid consultants on the state park and byway, but it seemed to John that Larson was the sole consultant, and that troubled him. He told me a group of historians, not one, should be consulted in developing these projects. His dissatisfaction led him to drop out of the working groups after a few years.

John and Larson also clashed over scholarship. “I critiqued him and he did not like it,” Larson said. “He needed to be challenged ... frankly, because he made a lot of mistakes.”

“He had a habit of sharing only selected primary sources,” Larson said, “and often left out crucial pieces of information that challenged the view he was presenting.”

Still, Larson credited John with some “amazing discoveries” and praised the depth and volume of his genealogical work: “His understanding of the landscapes of black and white families in Dorchester was remarkable. ... He deserves great credit for bringing a lot of the local black genealogical history to light.”

Despite all the people I’d talked to, I didn’t fully understand why John had investigated Tubman’s story so tirelessly.

John, Walsh said, faced a formidable puzzle, not just about Tubman and the escapees but the individuals in the Underground Railroad who helped them. Finding all the pieces was daunting, because it was a secret organization and its numerous black members never reported their experiences — due to illiteracy or fear of retaliation.

As for publishing, Lewis told me John always wanted to write Tubman’s biography and, in fact, started one in 1979, drafting about 60 pages before he stopped.

I asked her why she thought he never finished it. “He said he was a perfectionist,” she said. “He just didn’t figure he had enough information about Harriet Tubman.”

As his son Daniel saw it, publishing something on Tubman “was the expected thing [in] society. ... I think he saw that as being a lemming and doing what everybody else thought was the obvious thing to do.”

Larson believed that one reason he never wrote a book was because “he could not tolerate criticism or critical review of his work.” She also suspected he feared publication would expose mistakes. “Maybe he was constantly filled with self-doubt,” she said.

Or just maybe, instead of publishing his own work, he was, ultimately, content to share his findings directly with other historians, writers and artists. “Let a thousand flowers bloom,” he often said.

“John wrote the history on our minds,” said local historian Linda Duyer, a discussion-group regular. “He made each of us see how important the history is. ... This can be more powerful and lasting than a book.”

Peter Slavin is a Washington freelance writer and editor. To comment on this story, email wpmagazine@washpost.com or visit washingtonpost.com/magazine.

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