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Jimmy Hoffa -

Jimmy Hoffa, a prominent union leader in the 1960s, served as the president of the large US union, the Teamsters. Despite his fame, Hoffa's reputation was tarnished due to his involvement with organized crime, ultimately resulting in a prison sentence for corruption.

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Jimmy Hoffa -

After being released from prison, he vanished a few years later. He was last spotted at a Detroit eatery, supposedly in a meeting with two mob bosses. The Mafia is believed to have murdered him on the same day, but his remains were never discovered. Despite various leads, no crucial information has been uncovered, leaving his final resting place a mystery.

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Wolfgang Amadeus Mozart -

The talented Austrian composer passed away at the young age of 35. In September 1791, he fell ill and gradually became bedridden, experiencing symptoms such as pain, swelling, and vomiting.

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Wolfang Amadeus Mozart -

Despite his desperate efforts to complete his masterpiece 'Requiem,' the renowned composer passed away in December without achieving his goal. As per the customary practice during that era, he was laid to rest in a shared burial site. A gravedigger later claimed he had buried Mozart and could identify his skull, but tests on the skull were inconclusive.

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Leonardo da Vinci -

The esteemed Renaissance artist relocated to France during his final years, where he passed away at 67 years old. According to speculation, his final resting place is assumed to be the local church in Amboise, but confirming this has proven to be a challenge.

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Leonardo da Vinci -

The church of Saint-Florentin was ruined during the French Revolution, and it was decided to demolish and rebuild it. Sixty years later, an excavation uncovered some human bones and a chunk of stone that had a couple of letters from da Vinci's name. It's been proclaimed that the church is his resting place, but there's no way to confirm.

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Alexander the Great -

Alexander the Great, an esteemed emperor and conqueror, sadly met an unexpected end. At a mere 33 years old, he fell ill following a grand feast and ultimately passed away. It is theorized that his ailment may have been attributed to either malaria or poisoning. He was buried in a tomb made of pure gold. Needless to say, it was looted until there was nothing left.

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Alexander the Great -

Several emperors themselves engaged in looting. According to legends, the breastplate of Alexander was taken by the Roman emperor Caligula, while the Egyptian king Ptolemy IX had his coffin melted to create coins. Since 200 CE, the whereabouts of Alexander's remains have remained a mystery, resulting in various theories spanning from Australia to Venice.

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Glenn Miller -

Glenn Miller was a best-selling musician in the 1930s and 1940s, and has been called one of the greatest big-band leaders of all time. He joined the Airforce in World War II, where his musical skills came in handy! In 1944, he began a journey to France so his band could play for the troops in Paris.

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Glenn Miller -

However, his plane never arrived at its intended location. Miller, his two companions, and his aircraft vanished somewhere over the English Channel and were never seen again.

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Vlad the Impaler -

Vlad III, also known as Vlad the Impaler, was a leader known for his cruelty. Bram Stoker's 'Dracula' was inspired by him. His reputation for being blood-thirsty was a result of the brutal ways he dealt with his enemies.

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Vlad The Impaler -

Vlad was notorious for showcasing the bodies of his victims by impaling them on spikes, even when they were breathing. After his death at the hands of the Ottomans, his head was displayed on a spike to confirm his death. Nevertheless, the location of his body's resting spot remains a mystery.

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Genghis Khan -

Genghis Khan was another tyrant ruler, but unlike Vlad, he disappeared at his own request. He was in his sixties when he died, and it's believed he succumbed to long-term injuries he got when he fell off a horse.

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Genghis Khan -

On his deathbed, he insisted that he be buried secretly in an unmarked grave. After the slaves buried his body, they were killed. Then, the soldiers who killed the slaves were also killed. His system must have worked, as no one has been able to locate his remains to this day.

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Anthony and Cleopatra -

Cleopatra was the last and most notorious ruler of Egypt, and Mark Anthony was her famous lover. As their empire was falling to the Roman Emperor Octavian, the couple decided to kill themselves. Mark Anthony stabbed himself with a sword, thinking Cleopatra was already dead.

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Anthony and Cleopatra -

Cleopatra was captured but tragically met her end when a venomous snake bit her. Historians assert that Octavian allowed Cleopatra and Mark Antony to have a joint burial, although the exact location remains undisclosed.

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Harold Holt -

In 1966, Harold Holt was appointed as the Prime Minister of Australia. Sadly, in 1967, while swimming at his beloved beach, he vanished and was never found.

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Harold Holt -

Harry Holt's clothes were discovered untouched on the sandy beach, but no further evidence of his presence was ever found. Despite being an experienced swimmer, it is believed that he may have been taken out by the current or attacked by a shark. His death led to the creation of an expression, "doing a Harry Holt," which refers to an unexpected vanishing act.

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Oscar Zeta Acosta -

Oscar Zeta Acosta, a Mexican-American writer and activist, was the center of some controversies. He gained much recognition through his friendship with writer Hunter S. Thompson, who immortalized him as the character Dr. Gonzo in his renowned book 'Fear and Loathing in Las Vegas.' He was played by Benicio del Toro in the 1998 film adaption starring Johnny Depp.

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Oscar Zeta Acosta -

Acosta's fondness for recreational drugs is known to those familiar with the film. During his trip in Mexico, Acosta contacted his son and mentioned his intention to ride on a vessel containing "white snow." Unfortunately, he vanished without a trace thereafter. There are various theories surrounding his disappearance, such as potential conflicts with drug traffickers, a fatal overdose, or even targeted assassination due to political motives.

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Davy Crockett -

Davy Crockett, a well-known American frontiersman, has been revered as a prominent folk hero for many generations. Historical records confirm his death during the renowned siege at the Alamo amid the Texas Revolution. However, the precise circumstances of his death and his final resting place remain a mystery.

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Davy Crockett -

The individuals who perished at the Alamo were incinerated by the Mexican army. At the Cathedral of San Fernando, a marble receptacle allegedly holds the ashes of Crockett and various other courageous figures from the frontier. Nevertheless, historians express doubt that the ashes truly pertain to Crockett.

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Solomon Northup -

Solomon Northup, an African-American man, was kidnapped and forced into slavery. After a long struggle, he regained his freedom and chronicled his remarkable experiences in 'Twelve Years a Slave,' a memoir adapted into an acclaimed film in 2013, winning an Academy Award.

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Solomon Northup -

Regrettably, this did not mark the joyful conclusion to his tale. He assumed the role of a roving speaker and vanished in 1857 while traveling to Canada. Certain individuals speculate that he was once more abducted and traded into slavery, or was killed due to his beliefs opposing slavery.

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Jean Spangler -

Jean Spangler was a prominent figure in the entertainment industry during the Golden Age of Hollywood. On a particular day, she informed her family that she would be meeting her ex-husband to discuss child support, followed by a night-shoot for a movie. However, she never made it back home. Shockingly, her ex-husband denied having any plans to meet her, and it was discovered that no filming was scheduled for that evening.

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Jean Spangler -

It appeared that she may have intended to vanish, but after two days, her purse was discovered close to a park. The straps were damaged, suggesting that it had been forcefully taken off her shoulder. Despite the efforts of over 160 individuals who extensively searched the vicinity, no additional evidence could be found. The case remains unresolved till now. It's assumed she died when she disappeared in 1949 at the age of 26.

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Amelia Earhart -

Amelia Earhart may be the most famous missing person in the world. She earned her place in history as the first woman aviator to accomplish a solo flight across the Atlantic Ocean. In 1937, Earhart embarked on a widely publicized expedition to circumnavigate the world with her navigator. Unfortunately, their journey encountered difficulties after covering 22,000 miles (35,405 km) of the intended 29,000-mile (46,670 km) distance.

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Amelia Earhart -

Earhart sent out a distress call during her flight across the Pacific Ocean, indicating that they were running dangerously low on fuel. Despite rescue efforts, communication ceased and her plane was never found. Extensive searches at the time and in the subsequent century failed to uncover her whereabouts.

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Amelia Earhart -

Her disappearance has consumed historians, scientists, conspiracy theorists, and the regular American alike. Recently, forensic scientists began to believe they have confirmation that her bones were found. Does this mean we finally get closure?

Sources: (Mental Floss) (TV Over Mind)

See also: The most mysterious murders of all time

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