After discovering a talent for forgery during the Civil War, James Reavis headed west and started one of the most ambitious hoaxes of all time. He invented a Spanish nobleman named Miguel de Peralta, devised his entire family tree, and began assiduously forging documents claiming 10 million acres of prime Arizona land for the don’s descendants. Then he traveled throughout Spain and Mexico, carefully seeding libraries and archives with the forged deeds, mortgages, and wills.

When all was ready, he went before the U.S. surveyor general in 1881 and showed that rights to these lands now belonged to him. He imposed taxes on residents throughout Arizona, including the Southern Pacific Railroad and the Silver King Mine, but when their lawyers sought to challenge the claims they found Reavis’ carefully forged documents on file.

The ruse made Reavis one of the richest land barons in Arizona, and soon he’d bought mansions in New York, Washington, St. Louis, and Mexico. But it all lasted less than 10 years, unraveling in 1890 when a Spanish linguist detected the forgeries. Reavis served six years in prison and spent the rest of his life on the streets of Santa Fe.

In the 1840s P.T. Barnum found himself a victim of his own success. His New York museum of curiosities proved so popular that it was regularly filled to capacity and could admit no more customers.

Barnum studied the problem and hired a carpenter. Soon a new door appeared in the museum with a sign reading THIS WAY TO THE EGRESS.

Those who followed it found themselves on Ann Street.

Canada saw a sensation in 1836 — a woman named Maria Monk claimed to have been a nun in a Montreal convent where priests from the nearby seminary would enter through a secret tunnel, force sex on the terrified nuns, and dispose horribly of any resulting children:

[Father Larkin] first put oil upon the heads of the infants, as is the custom before baptism. When he had baptized the children, they were taken, one after another, by one of the old nuns, in the presence of us all. She pressed her hand upon the mouth and nose of the first so tight that it could not breathe, and in a few minutes, when the hand was removed, it was dead. She then took the other and treated it in the same way. No sound was heard, and both the children were corpses. The greatest indifference was shown by all present during this operation; for all, as I well knew, were long accustomed to such scenes. The little bodies were then taken into the cellar, thrown into the pit I have mentioned, and covered with a quantity of lime.

Awful Disclosures of Maria Monk became a bestseller, but an investigation showed that the whole thing had been a fake; Monk had apparently never even visited the convent. She fled to Philadelphia, wrote an unsuccessful sequel, had a child out of wedlock, and died in 1839.

“Spirit photographs” created by hoaxer William Hope in 1919.

From left: Mr. and Mrs. Gibson with their deceased son; Mrs. Longcake with her dead sister-in-law; the Rev. Charles Tweedale and his wife, with her father.

Arthur Conan Doyle (below, center) defended Hope even when skeptic Harry Price had shown that he was manipulating his plates. “The credulity of dupes,” wrote Edmund Burke, “is as inexhaustible as the invention of knaves.”

In 1885, explorer Richard Willoughby claimed to have discovered a wonderful mirage above Alaska’s Muir glacier: He’d seen a modern city, he said, with buildings, church towers, vessels, even citizens. This photograph sold “like hot cakes” in the summer of 1889, and Willoughby sold the negative to a San Francisco photographer for $500.

There it all unraveled. An American consul, home from England, noted that the “silent city” bore a striking resemblance to Bristol. It turned out that Willoughby had paid an English tourist $10 for an overexposed photo of his hometown, and the rest was hot air. Still, he deserves credit for invention.

Bata Kindai Amgoza ibn LoBagola told an inspiring story: Born in West Africa, he wandered to the sea at age 7 and found himself aboard a steamer bound for Scotland. From there he made his way to the United States, where he took up lecturing. His 1930 autobiography, LoBagola; An African Savage’s Own Story, gives vivid details about life in the bush:

“If you should climb a tree, the lion can easily get help from the elephant, because the elephant and the lion are friendly. … [T]he lion tells the elephant that it wants you down from the tree, and the elephant shakes the tree or pulls it up by the roots, and down you come.”

The truth was more prosaic: His real name was Joseph Lee and he was born in Baltimore. “Small opportunities,” wrote Demosthenes, “are often the beginning of great enterprises.”

When Gregor MacGregor returned to England from the New World in 1820, he brought auspicious news: He had been created prince of Poyais, a Central American nation of 12,500 square miles.

The Scottish soldier became the toast of London and was soon entertaining dignitaries at elaborate banquets. He published a glowing guidebook, raised a loan of £200,000 for his new government, and began selling land rights to excited settlers.

But when two ships arrived at the described location in 1823, they found nothing but jungle. Lacking shelter and beset by disease, the settlers had to be evacuated to British Honduras, and only 70 of the 250 survived. A warning reached London in time to stop five additional ships from making the voyage.

A furor erupted, but by that time MacGregor had left for France, where he attempted the same hoax. Officials there locked him up, but he was acquitted at trial and brazenly returned to England, where he kept up similar schemes through 1837. He died, blithely, in Venezuela in 1845.