Nathaniel Montague spent more than 50 of his 84 years chasing history, meticulously collecting rare and one-of-a-kind fragments of America's past. Slave documents. Photographs. Signatures. Recordings.

Montague -- Magnificent Montague, as he's been known since his days as a pioneering radio DJ -- amassed an 8,000-piece collection reflecting names from the well-known to the forgotten to those history never thought to remember. It's valued in the millions; some call it priceless. One assessment of just five of the pieces puts the total value of those treasures alone somewhere between $592,000 and $940,000.

"I shudder to even fantasize what it could go for," said appraiser Philip Merrill, who performed the assessment.

For decades Montague carted the collection of African-American artwork, artifacts and ephemera around the country with his family as he took jobs at radio stations in New York, Chicago, Oakland, and Los Angeles, and then finally to Las Vegas, where he moved 12 years ago after closing a station he built from the ground up in Palm Springs, California.

The Montague Collection was his prized possession, but because of financial woes he has lost it. It is now up for auction.

"I have not been able to maintain the collection for the last couple of years," Montague said. While working with his wife of 56 years, Rose Casalan, to archive and prepare the collection for sale, he took out a loan to help pay for the archiving, found himself overextended financially and declared bankruptcy. His collection was seized, and it is now in the hands of a trusteeship charged with selling it to satisfy his debts, including a judgment for $325,000 plus interest and court fees.

If no one steps up to buy the collection in its entirety, Montague's life's work could be dismantled and sold off in pieces to pay his creditors.

In the meantime, it is stored in a confidential location in Nevada.

Boxed and hidden under tight security in Las Vegas -- away from the city's bright lights and infamous Strip -- is the item that sparked his collection: a set of first-edition Paul Laurence Dunbar books Montague purchased in Washington in 1956.

"One day I stumbled into a book by Paul Laurence Dunbar," he said. Until that day, he had never thought of collecting memorabilia -- much less heard of Dunbar, author of novels, short stories and essays, and the first African-American to gain national acclaim as a poet.

"I bought the book, and I never looked back after that," Montague said.

It was the first time he saw the "Negro dialect" Dunbar was known for using in his early poetry, and it sparked his interest in African-American culture -- "the Negro problem," as it was called in periodicals in the 1950s.

"I began to learn who some of the blacks were in the 1800s and 1700s, and I was shocked. I said, 'Well, I have to do something about this.' So I started going to bookshops and visiting the dealers. And I would ask, 'Do you have anything black? Negro?'"

He looked for first editions and signed copies, no matter the cost. "I just had to have it," he said. "I had to bid my brains out."

He dug through magazine crates and traveled the country visiting rare book stores and auctions. He once traveled from Los Angeles to Germany to purchase "The African," an 1890 pastel drawing of an African king wearing traditional robes. It was drawn and signed by Austrian artist Rudolf von Mehoffer, who was known for his portraits of German and Austrian royalty.

"I would spend sometimes a day, hours, in a place going through old magazines, looking for something about the Negro. Something about the word 'colored.' Something about the word 'black,'" he said.

"I didn't collect; I chased," he said, making investments in time, money and energy that he says he cannot measure. "I was not writing history; I was chasing it."

For more than 50 years he memorized names of writers, artists and filmmakers, hunted them, found them, and added their works to his collection. There are pieces that inspire him, like the first edition of Phillis Wheatley's "Poems on Various Subjects," dated 1773 and signed by the author, who was born a slave and became the first African-American to have a published book.

There's a 1944 Fred Sapp oil painting of Toussaint L'Ouverture, leader of the rebellion that emancipated Haiti's slaves in 1801.

He also has pieces he considers historical yet repugnant, such as sheet music to the 1900 song "Coon, Coon, Coon" and a 1935 advertisement for "The World's Only Flying Negro Singers."

Also secured in the Las Vegas vault is a fundraising letter Booker T. Washington wrote seeking financial assistance for 221 students at Tuskegee, the college he founded in 1881. There are photographs, receipts and letters from the Lincoln Motion Picture Co., the nation's first all-black production company. Brothers George and Noble Johnson operated it from 1916 to 1923, producing five full-length films and other works they showed mainly in black churches and small assembly halls.

Montague acquired a copy of the Liberator, an anti-slavery newspaper published from 1831 to 1865, when the Civil War ended and the 13th Amendment was ratified, abolishing slavery.

There's the 1820 bill of sale for "Two Negro boys George + Paris," who were sold for a total of $1,230, and a contract with Negro Nancy, who with an "X" and a thumbprint agreed to a life of indentured servitude in Pennsylvania.

"I'd say I have 500 to 600 items that the public have never seen and will never see until they see the collection," Montague said, including memorabilia and recordings from his time as a DJ and radio station owner, where he recited poetry with soul music pioneer Sam Cooke, performed with R&B artist Wilson Pickett and coined the phrase, "Burn, Baby, Burn."

Montague says he came up with the phrase in 1962 while working at a station in New York. He was given a copy of Pickett's new song, "If You Need Me," and he fell in love with it.