EDINBURGH.- For more than 400 years, Richard III has been seen as Britain’s most infamous king — a power-hungry usurper who killed his young nephews to clear the way to the throne.

In Shakespeare’s “Richard III,” the king tells an assassin, “I wish the bastards dead,” referring to the princes Edward V and Richard. “And I would have it suddenly performed.”

But the king’s murderous image, drawn from history books and cemented in literature and lore, is just not true — or, at least, it has not been proved true, argues Philippa Langley, an author and independent historian.

“Maybe there is evidence,” she said over a cup of tea in Edinburgh this year. “But there seems to be no evidence.”

Langley is, perhaps, Richard III’s most dedicated living defender. A prominent member of the Richard III Society, an organization that has been working since 1924 “to secure a more balanced assessment of the king,” she has made a career of researching — and rehabilitating — a man who ruled for two years, from 1483 to his death in 1485.

In 2012, she spearheaded a project to find his remains, which were under a parking lot in the city of Leicester, as she believed they would be, and give him a dignified burial. Once she had laid Richard III to rest, however, she found she couldn’t quite let him go. After all, he was still seen as a murderer.

So she took on the case of the princes’ disappearance. Is there, she wanted to know, enough archival evidence to say beyond a reasonable doubt that Richard III ordered the assassinations of the boys? Was the king a murderer — or a victim of centuries of rumor and prejudice?

These are the questions at the heart of Langley’s most recent book, “The Princes in the Tower,” published in late 2023. In it, she takes a true-crime approach to the mystery, using what she describes as “the same principles and practices as a modern police inquiry.”

She wanted to find the truth, she said, even if it meant finding evidence that suggests that he was, indeed, a killer.

“It’s about making sure that the story we tell about this country is correct,” Langley, 62, said, adding, “Whether that is today or tomorrow or 500 years ago, evidence, truth, facts — rather than stories and lies — are really important.”

To the reading public in Britain and historians around the world, Langley is something of a curiosity. She did not attend university. And yet she became the face of one of the splashiest historical events of the century.

For finding Richard III’s body, she was awarded an MBE, a national honor. She is recognized at train stations, though not terribly often, she said. And she has earned the respect of many university scholars.

“I don’t think she got lucky with Richard III,” said Sebastian Sobecki, a professor of late medieval English literature at the University of Toronto. “She did very good research.”

He is one of many academics who acknowledge that Langley, who formerly worked in marketing and advertising, understands how to excite people about the past — more so, perhaps, than most academics. (How many historians can say they were played by Sally Hawkins, as Langley was in the film “The Lost King”?)

But even if some professors think of her work as worthy, many also see it as fundamentally unacademic. Serious scholars do not usually probe the past to find or exonerate long-dead kings, they argue.

“The reason that archaeologists hadn’t looked for him in the past is that archaeologists don’t go looking for famous dead people,” said Philip Schwyzer, a specialist in early modern English literature at the University of Exeter.

A few critics even see Langley as a charlatan. But most just think that she is naive, blinded by her own rosy image of the king.

That outlook builds on a long-standing skepticism of the Richard III Society. “It is frankly partisan in a war that ended more than 500 years ago,” said Spencer Strub, a humanities researcher at Princeton University, of the organization.

Langley knows what her detractors say about her, she said: She doesn’t have the right credentials. She’s emotional, a woman with a 15th-century crush.

But Langley fought for legitimacy well before discovering Richard III. For decades, she has lived with chronic fatigue syndrome, a condition that has long been met with skepticism from doctors and colleagues alike.

That’s part of what binds her to Richard III, Langley said. Studies of his skeleton showed that he had scoliosis — a physical condition long portrayed (and mocked) on the stage as a motivation for his rage across the centuries. “He would have been dealing with something that he had to hide,” she said. “And I was the same.”

And her work speaks for itself, Langley said: She did find his grave. And now, she thinks she has cracked a major historical cover-up.

The story stems from Richard III’s coronation, which happened amid a swirl of scandal.

His brother, King Edward IV, had died in the spring of 1483. Richard was made protector of the realm until the king’s eldest son and successor, 12-year-old Edward V, came of age. But before the boy was crowned, his parents’ marriage was declared illegitimate and his coronation was suspended.

Richard III was proclaimed king instead. Soon after, the boy and his younger brother, Richard, 9, disappeared from where they had been held, the Tower of London.

That, Langley argues, makes it a missing persons inquest, not a murder case. “This was all we knew for certain, based on the available evidence,” she writes.

She argues that the dominant narrative — that Richard III had the princes killed to take the throne — is little more than rumor that calcified into fact over 500 years. Instead, she suggests, the boys were alive when Richard was crowned.

Richard III was the last king in England’s Plantagenet line. Henry VII, who ousted him, was the first Tudor king; he had a dynasty to establish, a reputation to build. So, Langley argues, Henry VII cast his predecessor as a villain.

It would also have been useful for the Tudors if people thought the boys were dead, unable to fight for the throne, Langley writes in the book. Rumors of their deaths started under Henry VII, she notes, pointing to texts from Richard III’s reign that talk about his nephews in the present tense.

That’s why she thinks that the boys weren’t killed — at least not in the Tower of London, in 1483. Instead, she argues, they were smuggled out of the British capital. Then, after Richard III was killed and the princes were made legitimate again, she argues that they both tried to retake the throne, Anastasia-like.

She weaves her argument out of archival material gathered over seven years by a team of more than 300 independent researchers. The evidence includes receipts for weapons; a witness statement describing the boys’ flight; royal seals and more. To complicate matters, Langley also argues that both of the princes were later given false identities by the Tudor government: They were described as impostors trying to pose as princes, not the real thing.

“Apparent red herrings seemed to litter the story,” she writes. “The project could not afford to miss anything, no matter how seemingly insignificant.”

Langley also tries to debunk some of the historically accepted pieces of evidence in support of the view that the nephews were assassinated, the so-called eyewitness testimonies. One, from Sir Thomas More, was written decades after the fact — under the Tudors. She argues that another, penned by an Italian monk who was in London in 1483, does not say the boys were murdered — only that he didn’t know what had happened to the older boy.

The accounts are not proof, she says.

Many top academics agree that the often cited accounts for the princes’ murder are thin. “People realize how flimsy the evidence is,” said Schwyzer, the scholar of early modern English literature. “The most reliable reports say they went into the tower and were seen less and less often, and people thought they were dead.”

For Langley’s argument to prevail, she must first explain the skeletons of young children that were found in the tower in 1674. The bones were examined in 1933. They are interred at Westminster Abbey as the supposed remains of the princes.

“How many children would have been put in a box and buried under a staircase in the tower?” said Raluca Radulescu, a professor of medieval literature and a cultural historian at the University of Bangor, in Wales. “Like, why?”

Langley has an answer there, too.

The remains have not undergone modern scientific analysis or DNA testing, she notes. That would require approval by the Dean of Westminster in consultation with the royal household.

“The view of previous deans has always been that the mortal remains of two young children, widely believed since the 17th century to be the princes in the tower, should not be disturbed,” said Victoria Ribbans, a spokesperson for the Abbey. “There are no current plans to change this.”

Within the Tower of London itself, speculation is afoot.

Julian Jennings, a warden who has worked there for more than 18 years, is fascinated by the history he protects. He even traveled to Leicester when Richard III was reinterred in 2015, just to be present.

He’s been following the debate about Langley’s book, and he’s bursting to talk about it. When asked for directions — with no mention of the princes — he brought up the debate. “It’s an absolute minefield,” he said.

Jennings is still making up his mind on the matter, he said. But a few stories below, the long-standing narrative is codified on a plaque: “The tradition of the tower has always pointed out this as the stair under which the bones of Edward the 5th and his brother were found.”

The research Langley put forward, he said, could well be the biggest historical shake-up in a long time. He and his colleagues are abuzz with wonder: What if the princes actually lived?

The question is a testament to Langley’s influence.

“It’s good to keep an open mind,” he said, during a recent shift. “At least I do, anyway.”

This article originally appeared in The New York Times.