It's arguably one of the most significant discoveries in the history of the world, accomplished by an improbable collection of characters through a complex series of improbable developments.

Yet few are aware of the find – for reasons that become evident as the saga is told – and even fewer know the whole story and the threads the players wove into the events of World War II and their influence on its outcome.

The discovery was the bones of the Apostle Peter, a scientifically verified find that was authenticated only recently under the leadership of Popes Benedict and Francis. The search also uncovered startling new evidence – hidden for nearly two millennia – of a thriving Christian community rooted in belief in the divinity of Jesus Christ at a time of intense Roman persecution.

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The storyteller, in the newly released book "The Fisherman's Tomb," is perhaps as improbable as the story. Yet, like the characters, perfectly positioned.

John O'Neill is known as the face of the Vietnam swift boat veterans who many believe prevented John Kerry from being elected president of the United States in 2004. (O'Neill and the more than 200 veterans who came forward still stand by their story despite the establishment media's boilerplate dismissal of "discredited claims.")

O'Neill, a retired Houston lawyer, was co-author of the New York Times bestseller that rocked the 2004 election, "Unfit for Command," the bible of the campaign of Swift Boat Veterans for Truth, and "The Fisherman's Tomb," is his first book since then.

This time, amid a cynical culture that disregards the claims of Christianity as myth, he endeavors to set the record straight and tell for the first time the whole truth about the 75-year search for Peter.

A skeptic himself by nature, O’Neill makes the case in a well-written, engaging, novelistic fashion, undergirded by his lawyerly reliance on reason and verifiable evidence.

It's the story of a risky, top-secret endeavor launched in 1942 that never could have been accomplished without the help of a humble, enormously wealthy and generous Texas oilman whose lifelong insistence on anonymity and his belief that he was a partner with God in his vocation made him a perfect accomplice.

It was O'Neill's friendship with the son and other descendants of the late oilman, George W. Strake Sr., his familiarity with oil exploration as a senior partner for a large international law firm in Houston, personal interest in archaeology, lifetime of researching complex global matters and faith in God that compelled him to write the book.

"Sometimes a story finds an author rather than the reverse," writes O'Neill in the foreword, noting he had resolved not to write again after "Unfit for Command," despite many offers.

"It's a shocking combination of all kinds of serendipitous circumstances, and it's hard not to attribute it to anything but God wanting the story out," said O'Neill in an interview with WND.

Even more against all odds is the story itself.

It took Strake becoming immensely wealthy through the unlikely discovery of the country's third largest oil field during the Great Depression in an area near Houston every other "wildcatter" had given up on, O'Neill noted. It required the uncovering of clues through the digging of a grave for a deceased pope, the courageous vision of his papal successor to pursue it – the gamble of disproving church tradition or providing earth-shattering, faith-building evidence – and a workman falling through a floor into an unknown, wondrous underground realm of color-rich Roman antiquities. And it couldn't have been done without a brilliant, uniquely equipped, female pioneer archaeologist who entered the project as a devoted scientist with no religious faith and finished it as a believer.

The archeologist, Margherita Guarducci, was a genius, O'Neill said, and "probably the only person who could have decoded everything to find Peter."

According to church tradition, Peter, one of the three disciples closest to Jesus, was executed in Rome and chose to be crucified upside down, because he thought himself unworthy to suffer precisely as Jesus did. But until Guarducci's find, there was scant evidence the great apostle had even been in Rome.

The discovered bones, at a site predicted by church tradition but dismissed by naysayers, were of a robust 65-year-old man who bore the marks of violent crucifixion.

Guarducci homed in on the site after deciphering coded inscriptions that declared: "Peter is here."

Without attribution or credit

Strake was listed on the Fortune 50 as one of the wealthiest persons in the United States in the mid-1960s, even after he already had given away hundreds of millions of dollars.

The Conroe oil field he discovered in 1931 pumped out 500 million barrels of oil that became the lifeblood of the allies during World War II. Along with funding the search for Peter, he assisted Pope Pius XII in helping Jews evade the Nazis. And after the war, when communism threatened to gain a foothold in Western Europe through Italy, he helped the pope start small parish churches to provide competition to the communists, leading to the party's defeat in the crucial elections of 1948, the year Stalin seized power in several East European countries.

"All of these things done without attribution or credit, " O'Neill said, noting there is no Wikipedia entry for George Strake Sr., although there is one for his accomplished son, George Jr.

Another key figure in the story who shared the common attribute of eschewing fame and glory was Walter Carroll, a trusted confidant of the initiator of the search, Pope Pius XII. It was Carroll who was secretly dispatched to Houston to ask Strake to sign a blank check for a totally secret "wildcat" project of doubtful success.

Carroll also risked his life as a liaison behind enemy lines, carrying messages to the allies. Without him, according to Gen. Dwight D. Eisenhower's chief of staff, Rome might have been lost.

Why don't we know this story?

A major reason the remarkable discovery of Peter isn't well known is because of the fierce denunciation of Guarducci's work by Father Antonio Ferrua, a Vatican archaeologist who led the search initially and claimed to have found the disciple's bones after a decade of work. But not long after Ferrua and his team were celebrated in a Time magazine cover story in 1950, Guarducci was invited to tour the excavation site, and she found that Ferrua had made a "terrible mistake." Pope Pius XII then put Guarducci in charge, and her team not only disproved Ferrua's claims, it found another site, another set of bones and a wealth of convincing evidence that she had found Peter.

Ferrua later regained control of the effort, fired Guarducci and vehemently denounced her and her find.

In 2004, The Atlantic magazine published a glowing article about Ferrua, concluding he has disproved Guarducci's claims.

But in a 1990 symposium in Milan on Guarducci's finds, the moderator, the head of Sotheby's Europe and the greatest expert in Roman antiquities in the world, Federico Zeri, stood up to speak.

He described himself as an agnostic who didn't believe in Christianity. But there's no question, he insisted, that Margherita Guarducci, whom he called a "diamond bit for the truth," has found Peter.

At the conference, Guarducci, then in her 90s, gave an impassioned speech.

"They've said that my faith controlled my science, but I had no faith until I had science," said Guarducci, according to O'Neill's paraphrase. "My science is what produced faith."

Pope Benedict commissioned an examination of her discovery and concluded the science was solid, and she indeed had found Peter. Shortly after Francis became pope, he held a box of the bones and declared them authentic in front of a crowd of about 7,000 people at the most important mass of the year, saying, "Behold the relics of Peter."

'I'm a doubting Thomas'

O'Neill emphasized "The Fisherman's Tomb," published by Our Sunday Visitor, is not a book only for Catholics but for all Christians and for anyone evaluating the claims of Christianity. O'Neill himself is a member of a Presbyterian church in Houston.

"First, it's a great adventure, a detective story, with Nazis marching outside, with the purported curse the workmen claimed in the ruins," he told WND.

He noted the inscriptions found around Peter support the fundamental beliefs of all Christians.

Some scholars have claimed Christianity was an evolving cult and that Christians didn't believe in the divinity of Christ until much later.

"Those inscriptions were carved in stone by the earliest Christians, depicting basic beliefs in redemption and an afterlife," he said. "You could be killed if found carving this."

Before Guarducci, the inscriptions were dismissed as meaningless and indecipherable.

O'Neill said that, personally, he tends to be a doubter.

"It's my nature. My wife is a wonderful person, of fabulous faith. I'm a Thomas, a doubter," he said.

But anyone who goes on the Scavi Tour at the Vatican can "put your hands here on these walls, you can take a look at these relics."

"And even a doubter like me ceases to doubt," he said.

"I was a pretty good lawyer, and I tried an awful lot of cases. I would be afraid to try the other side of this case," said O'Neill, a graduate of the Naval Academy and a former law clerk to Supreme Court Chief Justice William Rehnquist.

"This is a slam dunk on [Guarducci] having located Peter. And it is a slam dunk on those inscriptions. Those are very fundamental to anyone who has any doubts about Christianity."

Thank you, thank you, thank you

O'Neill has found that virtually everyone who reads the story is amazed, having never heard of it or having been completely unaware of the role of George Strake.

Despite an establishment media blackout, the book has topped many bestseller categories on Amazon and has risen as high as No. 125 overall.

At a launch for the book in Houston attended by more than 400 people, 22 members of the Strake family were in attendance.

O'Neill directed his words to the family, commenting that the only bad thing about giving things away anonymously is that nobody gets to say thank you.

"We've got all of you here, and I would like to say thank you for all of those Jewish folks you saved during the Second World War, for all the people whose freedom you saved, for all the people whose faith you made stronger through this excavation," he said.

"So thank you, thank you, thank you."

O'Neill said the family had to think long and hard about whether or not to let the story out.

"They had to decide if it was compatible with what George Senior wanted to do. They finally decided that letting people know about the whole story was more important after this length of time than his wish for anonymity so many years ago," he told WND.

The story raises many questions for the reader, and O'Neill asks one directly to conclude the book: "Quo Vadis," a Latin phrase that evokes a legendary tale about Peter, meaning, "Where are you going?"

"I think sometimes people shuffle through life and they don't realize it's going to come to an end," he said. "They don't realize it's not just about the things they accumulate."

Greatest people I ever knew

About John Kerry, O'Neill said, "I'm sorry for him; I hope that some day he comes around."

"I guess the election actually showed whether we were discredited or not. I'm content with the result of that election as a judgment," he told WND.

Referring to Kerry's characterization of troops in Vietnam as criminals, O'Neill said the "greatest people I ever knew were the people I served with in Vietnam."

"And they were not criminals. They were fabulous, wonderful people fighting for a great cause," he said.

"Until the last breath I breathe, I will be so proud of the fact that I actually knew them and got the chance to serve with them, including the ones we lost who didn't come home."