5 Enduring Historical Mysteries That Have Since Been Solved

In 525 BCE, Persian King Cambyses II sent more than 50,000 soldiers into the Egyptian desert. They were never heard from again. “A wind arose from the south, strong and deadly, bringing with it vast columns of whirling sand, which entirely covered up the troops and caused them wholly to disappear.” That’s according to classical Greek historian Herodotus who, for centuries, was our only source of information about the lost army.

Indeed, many historians believed that the story was nothing more than a myth until 2009, when Italian brothers Angelo and Alfredo Castiglioni discovered evidence suggesting that the army had, in fact, been swallowed by the sands. Deep in the desert, they found Persian artifacts and, what’s more, a mass grave containing hundreds of bleached bones.

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Nor was that the end. “Experience has long shown that you cannot die from a sandstorm,” Olaf Kaper, Professor of Egyptology at Leiden University in the Netherlands, said while presenting his findings at the International Conference of the European Research Council in 2014. The evidence that Professor Kaper found suggests that the lost army may actually have been ambushed in the desert by forces under the command of Egyptian rebel leader Petubastis III.

Perhaps the most famous “ghost ship” of all time, the American merchant vessel Mary Celeste was found abandoned and adrift off the Azores Islands on December 4th, 1872. There was no apparent cause of the crew abandoning ship. Indeed, most of their personal possessions were still there, undisturbed.

For years, the mystery of the abandoned ship has haunted us. It has inspired poems and songs and not a few films, going back at least as far as 1935’s Mystery of the Mary Celeste, an early film from Hammer Film Productions starring Bela Lugosi. Even Sherlock Holmes creator Arthur Conan Doyle took an early swipe at the story of the Mary Celeste, writing about it in a tale published in Cornhill Magazine in 1884.

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What really happened to the crew of the mysterious ship, though? We may never know for certain, but in recent years, scientists have put forth what is probably the most likely hypothesis. The Mary Celeste was carrying a cargo of some 1,700 bottles of denatured alcohol. According to an experiment conducted by Dr. Andrea Sella of University College, London, it’s possible for the alcohol to have caught fire in what has been called an “invisible explosion,” panicking the crew enough that they might abandon ship without damaging the vessel itself.

“What we created was a pressure-wave type of explosion,” Sella said of the experiment. “There was a spectacular wave of flame but, behind it, was relatively cool air. No soot was left behind and there was no burning or scorching.”

In 1908 something seemingly inexplicable happened in a remote part of Siberia. 830 square miles of forest were flattened in just seconds, releasing an amount of energy estimated to have been 1,000 times greater than that of the atomic bomb that was dropped on Hiroshima.

For decades, the “Tunguska event,” as the mysterious phenomenon was known, was one of the most perplexing pieces of paranormal lore around. The blast was attributed to everything from secret superweapons to UFOs to time travel, with less fanciful suggestions including that the Earth may have been struck by a comet.

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More recently, scientists have concluded that the Tunguska event was most likely caused by an air burst, in which a meteor explodes mid-flight as it travels through Earth's atmosphere. This would explain why a fireball and blast wave occurred even though an impact crater has not been found on the Earth's surface. Computer simulations have supported this theory.

In the dead of night, between July 16th and 17th of 1918, Czar Nicholas II, last emperor of Russia, and his wife and children were executed by Bolshevik revolutionaries. Because of the secrecy of the act, rumors persisted for years that the family’s youngest daughter, Anastasia, had survived and been secreted out of the house to safety.

The story so gripped the public imagination that it gave rise to countless books, songs, and even movies. Over the decades that followed, numerous pretenders came forward claiming to be the young heiress to the Russian throne, but none proved to be the real deal, perhaps because she didn’t actually survive.

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In 1991, the remains of Czar Nicholas, his wife, and three of their children were discovered, but that still left two unaccounted for. So, people continued to hope that perhaps Anastasia had gotten away after all. At least until 2007, when a second unmarked gravesite was discovered, containing the bodies of two other children. The identities of all the remains were eventually confirmed via DNA testing, meaning that, as good as the story of her miraculous survival might have been, Anastasia actually perished alongside her family.

It was in December of 1942, a year and a day after the Japanese attack on Pearl Harbor, when radar located an unidentified aircraft. Two fighters scrambled to intercept and what they saw amazed them. Instead of an enemy attack, they encountered an American P-40, already an antique, its fuselage shot full of holes and its pilot seemingly dead at the controls. Yet, just before the plane crashed, the pilot seemed to revive and wave weakly at the two fighters.

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That’s the story, more or less, as it has been told and retold time and again over the years, repeated as one of the most inexplicable mysteries of World War II. Inexplicable, perhaps, because it never actually happened. The story was actually a piece of fiction, written by real-life World War II flying ace Robert Lee Scott, Jr., who later wrote several books, including his 1943 autobiography, God is My Co-Pilot, which was turned into a hit film in 1945.

The story of the Pearl Harbor ghost plane seems to be a variation of the first chapter of his book of World War II fiction, Damned to Glory, with the location swapped to Pearl Harbor from the Kienow Airdome in China. When asked about the story years later, Scott reported said that he had no idea it had ever been repeated as fact, and that he wouldn’t have written it had he ever thought it would be.

Sources: NBC News, Archaeological Institute of America, University College London (UCL), NASA, Encyclopedia Britannica, Skeptoid