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What killed George Washington? -

The story of how Washington died on December 14, 1799, is a tale of a throat infection. Supposedly, he caught it after he was out riding in the freezing rain. He returned home in soaked clothes and subsequently attended dinner.

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What killed George Washington? -

There is doubt, though, that something as simple and common as a throat infection was what killed him. Some have speculated that perhaps he actually had strep throat, pneumonia, or something worse.

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What killed George Washington? -

It's even suggested that his death was a result of the bloodletting treatments he received. According to sources, over 80 ounces of blood, or a whopping 40% of his total blood volume, was drained from Washington.

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Has there already been a gay president? -

There is speculation and an ongoing mystery surrounding former President James Buchanan. To this day, he is the only unmarried president to have served in the United States.

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Has there already been a gay president? -

Buchanan, who was the 15th US president, was known for his close friendship with fellow senator William Rufus DeVane King. Both were said to be uninterested in marriage.

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Has there already been a gay president? -

Though not being married and having male friends doesn't necessarily mean someone is gay, it still leads many to wonder. There was even gossip around the capital where the former president and his friend the Senator were referred to as "Mr. Buchanan and his wife."

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How did Zachary Taylor die? -

Zachary Taylor was both a war hero and the 12th US president. However, he only made it slightly over a year into his first term when he died in July 1850.

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How did Zachary Taylor die? -

When he grew ill after a public appearance on July 4, doctors blamed cholera morbus (an old-fashioned term for gastroenteritis) as the cause of Taylor's demise. Some feared that it wasn't his most recent meal that made him ill but perhaps a popular poison of that time: arsenic.

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How did Zachary Taylor die? -

In 1991, Taylor's family had his remains exhumed and studied. A "normal" amount of arsenic for someone from that period was found in his system. However, many remain skeptical about how exactly he died.

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Was Lincoln really the subject of a Confederate conspiracy? -

Most people know the narrative behind the 1865 Lincoln assassination. As the story goes, a semi-famous actor named John Wilkes Booth, alongside criminal friends of his, plotted the murder. Many suspect, though, that the plan was orchestrated by the failing Confederacy.

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Was Lincoln really the subject of a Confederate conspiracy? -

Amateur historians such as James O. Hall, who was said to be an expert on the Lincoln assassination, believe that Booth was actually a Confederate agent who had been cut off from communication during the final days of the Civil War.

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Was Lincoln really the subject of a Confederate conspiracy? -

Despite supposed accounts of suspicious behavior such as Lincoln receiving unexplained payments from high-ranking officials, there is no definitive evidence that he was part of a wider Confederate conspiracy theory. However, some still aren't convinced.

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Was Chester Arthur Canadian? -

According to Article II, Section 1, Clause 5 of the U.S. Constitution, "only those who were citizens at the time the Constitution was adopted or who were born within the new nation thereafter could become president." Despite this, some have alleged that Chester Arthur was actually a Canadian citizen.

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Was Chester Arthur Canadian? -

It's speculated that he was born in Quebec, and there is a lot of confusion tied to the fact that there were six children in his family. Birth records were inconsistent and even destroyed in some cases due to a fire.

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Was Chester Arthur Canadian? -

It has been reported that when Arthur was asked to prove his US birth, he made an undisclosed trip to Canada. The truth is still cloudy today and many still wonder if he was actually Canadian. 

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What really killed Franklin D. Roosevelt? -

President Franklin D. Roosevelt (FDR) died on April 12, 1945, while in office. Officially, he died of a cerebral hemorrhage when he was at his retreat in Warm Springs, Georgia. Though the public was quite shocked, FDR's inner circle was less surprised as they knew he had been battling several health concerns. 

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What really killed Franklin D. Roosevelt? -

However, there is doubt about whether the hemorrhage was really the nail in his coffin. In a 2006 paper published by the Archives of Dermatology, the author pointed out a lesion on his head that had appeared to grow as he aged.

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What really killed Franklin D. Roosevelt? -

Others have taken this lesion theory and speculated further that perhaps FDR had melanoma that had metastasized into advanced cancer. However, without a tissue sample or other first-hand information, these claims will remain unproven.

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Did JFK have an affair with a Soviet spy? -

John F. Kennedy (JFK) was one of the youngest presidents elected in US history. It was said that while he was very charismatic, he also had a darker side that involved cheating on his wife.

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Did JFK have an affair with a Soviet spy? -

JFK had a mistress named Ellen Rometsch who was married to a West German army officer. She was known for engaging with high-powered political men who visited the private Quorum Club in Washington, D.C.

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Did JFK have an affair with a Soviet spy? -

The FBI speculated that Rometsch might be a spy, and she was deported due to her dangerously close connection with the President. Whether or not she was really a spy remains a mystery. 

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Did Jimmy Carter see an alien spacecraft? -

In 1969, former President Jimmy Carter reported seeing a "swiftly moving light on the western horizon." He also mentioned that it was as large as the moon but then changed size and shape rapidly.

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Did Jimmy Carter see an alien spacecraft? -

The incident wasn't reported until 1973 when he told UFO investigators he didn't believe what he saw was extraterrestrial. Some said that perhaps Carter saw the planet Venus.

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Did Jimmy Carter see an alien spacecraft? -

In 2016, a retired Air Force scientist proposed that Carter had seen electrically charged barium glowing in the atmosphere after a rocket launch at the Eglin Air Force Base in Florida. This still remains a mystery for many.

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Nixon’s missing tapes -

President Richard Nixon resigned from office on August 8, 1974, after his reputation was tainted by the Watergate scandal. Though he claimed he was innocent, there is still a lot of controversy around the tapes.

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Nixon’s missing tapes -

During the Watergate scandal, Nixon was ordered to produce the tapes for the Senate. However, 18.5 minutes was mysteriously missing. The secretary claimed the erased segment was an accident on her part.

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Nixon’s missing tapes -

Many wonder if incriminating parts of a conversation were erased. Experts have tried to recover the lost minutes but without success.

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Where is JFK’s brain? -

On November 22, 1963, JFK was shot in the head while in a motorcade and died. It's generally agreed that Lee Harvey Oswald acted alone in the assassination of JFK.

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Where is JFK’s brain? -

Kennedy's injury to the head meant that the brain could have been very important to investigate. However, during the autopsy, the brain was removed and locked in a metal box that was given to the Secret Service and moved to the White House. Later, his brother Robert moved the brain to the National Archives.

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Where is JFK’s brain? -

By 1966 however, there was no record of the brain in the National Archives, leaving many to speculate and wonder where it went and how it could've answered questions related to his life and death. It could have been a simple bureaucratic mix-up or, according to some, a way to hide how ill or heavily medicated JFK was at that time.

Sources: (Grunge) (Reader's Digest)

See also: Surprising facts about all 46 US presidents

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