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From JFK to 9/11: Examining the Most Famous Conspiracy Theories in History

Image of the moon walk during the Apollo 11 mission for a blog post covering famous conspiracy theories.

From the moon landing to the JFK assassination, famous conspiracy theories have captivated and divided people for generations.

These tantalizing tales of secret plots and hidden truths have a way of capturing our imagination and sparking heated debates.

In this post, we’ll dive deep into 11 of the most enduring and influential conspiracy theories, exploring their origins, evidence, and impact on society.

The Details: History’s Most Famous Conspiracy Theories

Kicking off our list of famous conspiracy theories is the granddaddy of them all: the JFK assassination.

The untimely death of President John F. Kennedy in 1963 has spawned countless conspiracy theories, with many claiming that the official lone gunman explanation is a cover-up for a much deeper and more sinister plot.

Image of President Kennedy's assassination as reported in the Springfield (Mass.) Daily News for a blog post covering famous conspiracy theories.
President Kennedy’s assassination is reported in the
November 22nd evening edition of the Springfield (Mass.) Daily News

1. JFK Assassination Conspiracy

The assassination of President John F. Kennedy in 1963 has sparked numerous famous conspiracy theories over the years.

While the official investigation concluded that Lee Harvey Oswald acted alone, many believe there was more to the story.

Some theories suggest the CIA, the Mafia, or even Vice President Lyndon B. Johnson were involved.

The motives behind these alleged conspiracies vary.

Some claim it was a political power grab, while others believe it was to prevent JFK from pulling out of Vietnam or revealing sensitive information.

Regardless of the truth, the JFK assassination remains one of the most enduring and well-known conspiracy theories in history.

Its impact on popular culture is still felt today, with countless books, movies, and documentaries exploring the various theories and keeping the public’s fascination alive.

For more on the Kennedy assassination check out my article 9 U.S. Presidents Who Died in Office and Their Stories

Image of an astronaut's footprint from the Apollo 11 moon landing.
An astronaut’s footprint from the Apollo 11 moon landing

2. Moon Landing Hoax

The Apollo 11 mission, which resulted in the first moon landing in 1969, is the subject of one of the most famous conspiracy theories.

Despite overwhelming evidence to the contrary, some people believe that the moon landing was an elaborate hoax staged by NASA.

Conspiracy theorists point to supposed anomalies in photographs and videos, such as the waving flag, the lack of stars in the sky, and alleged inconsistencies in shadows.

Proponents of this theory suggest various motives for the alleged hoax, such as the desire to win the Space Race against the Soviet Union or to distract from domestic issues.

However, experts and scientists have thoroughly debunked these claims, citing the existence of independent verification from other countries and the sheer difficulty of maintaining such a large-scale hoax.

Moreover, the technology needed to fake the moon landing did not exist at the time.

Despite the evidence, the moon landing conspiracy theory persists, demonstrating the enduring appeal of these types of famous conspiracy theories in popular culture.

Image of a sign on the city limits of Roswell, New Mexico.
The city limits of the town at the epicenter of UFO-related conspiracy theories, Roswell, New Mexico

3. UFO Cover-Up

The UFO cover-up conspiracy theory is one of the most well-known and enduring famous conspiracy theories.

It suggests that the U.S. government, and possibly other world governments, have been concealing evidence of extraterrestrial life and UFO visitations.

This theory gained traction following the alleged Roswell incident in 1947, where a UFO was said to have crashed in New Mexico.

Conspiracy theorists argue that the government has been suppressing witness testimonies, hiding physical evidence, and engaging in a massive cover-up to keep the public in the dark.

Proponents of this theory speculate about the motives behind the alleged cover-up, such as preventing mass panic or maintaining military technological advantages gained from studying alien technology.

However, skeptics and experts have questioned these claims, pointing out the lack of conclusive evidence and the possibility of misinterpretations, hoaxes, or natural explanations for UFO sightings.

Despite the absence of definitive proof, the UFO cover-up conspiracy theory persists, capturing the imagination of people worldwide and heavily influencing popular culture and science fiction.

Image of the pre-9/11 New York city landscape for a blog post covering famous conspiracy theories.
The pre-9/11 New York city landscape

4. 9/11 Inside Job

The 9/11 inside job conspiracy theory is among the most controversial and divisive famous conspiracy theories.

It suggests that the September 11, 2001 attacks, which claimed the lives of nearly 3,000 people, were orchestrated by elements within the U.S. government rather than carried out by Al-Qaeda terrorists, as the official investigations concluded.

Proponents of this theory argue that the collapse of the Twin Towers and World Trade Center Building 7 resembled controlled demolitions, that there was a lack of plane wreckage at the Pentagon, and that some government officials had foreknowledge of the attacks.

Conspiracy theorists propose various motives for the alleged inside job, such as justifying wars in the Middle East or expanding government control and surveillance.

However, experts and investigators have refuted these claims, citing a lack of evidence for controlled demolition, the presence of plane wreckage at the Pentagon, and the logistical impossibility of orchestrating such a large-scale conspiracy without detection.

It is crucial to approach this sensitive topic with respect for the victims and their families.

Despite evidence to the contrary, the 9/11 inside job conspiracy theory persists, impacting public discourse and trust in government institutions.

Image of the symbol of the Illuminati on a building's façade.
The symbol of the Illuminati on a building’s façade

5. Illuminati World Domination

The Illuminati world domination conspiracy theory is one of the most well-known and enduring famous conspiracy theories.

It alleges that a secret society, known as the Illuminati, founded in Bavaria in 1776, has been controlling world events, governments, and financial institutions to establish a New World Order.

According to conspiracy theorists, powerful individuals, families, and organizations, such as the Rothschilds, Rockefellers, and the Bilderberg Group, are involved in this centuries-old plot to dominate the world.

However, skeptics and historians have questioned these claims, citing a lack of credible evidence and the historical context of the original Illuminati group, which was disbanded by the Bavarian government in 1785.

Despite this, the Illuminati conspiracy theory has persisted and evolved, capturing the imagination of people worldwide and influencing popular culture, as well as shaping public perception of power structures.

While entertaining, it is essential to approach this theory with a critical mind and to rely on factual information from reliable sources.

Image of a child receiving a vaccine from a nurse.
A child receives a vaccine from a nurse

The vaccine autism link conspiracy theory is one of the most notorious and harmful famous conspiracy theories of recent times.

It originated with Andrew Wakefield’s now-discredited 1998 study, which suggested a link between the MMR (measles, mumps, and rubella) vaccine and autism.

Conspiracy theorists allege that pharmaceutical companies and health authorities are covering up this supposed connection to protect profits and avoid liability.

The appeal of this theory lies in its offer of a simple explanation for the complex issue of autism and the mistrust some people have in medical institutions.

However, the scientific community has overwhelmingly rejected this theory, citing numerous studies involving millions of children that have found no link between vaccines and autism.

The persistence of this debunked theory has led to decreased vaccination rates and the resurgence of preventable diseases, putting public health at risk.

It is crucial to rely on credible scientific evidence and the consensus of medical experts when making decisions about vaccination, rather than falling prey to unfounded conspiracy theories that can cause real harm.

Image of one of the world's most famous conspiracy theories, the flat earth.
Concept image of one of the world’s most famous conspiracy theories, the flat earth

7. Flat Earth Theory

The flat earth conspiracy theory, one of the most notorious famous conspiracy theories, has its roots in ancient times but has resurged in modern conspiracy circles.

Flat earth proponents argue that the earth is a flat disc rather than a globe, citing the alleged lack of visible curvature and supposed holes in the globe model.

They believe that there is a conspiracy to hide the earth’s true shape, often driven by a general distrust in scientific institutions and the appeal of questioning established knowledge.

However, the overwhelming scientific evidence supports the earth’s spherical shape.

Satellite imagery, circumnavigation, and observable phenomena like eclipses and the Coriolis effect all demonstrate that the earth is indeed a globe.

Despite this, the flat earth conspiracy theory persists, highlighting the importance of critical thinking, scientific literacy, and the need to rely on empirical evidence rather than unfounded claims.

By promoting scientific consensus and discouraging the spread of misinformation, we can help ensure that facts, rather than conspiracies, shape our understanding of the world.

Image of contrails from numerous aircraft marking the sky.
Contrails from numerous aircraft mark the sky

8. Chemtrail Mind Control

The chemtrail mind control conspiracy theory is one of the more recent famous conspiracy theories to gain traction.

Proponents of this theory believe that the condensation trails left behind by aircraft, known as contrails, are actually “chemtrails” containing mind-controlling chemicals deliberately sprayed by the government.

They argue that these chemicals are used for various nefarious purposes, such as population control, weather manipulation, or mass inoculation.

However, there is no scientific evidence to support the existence of chemtrails.

Experts explain that contrails are formed when hot, humid exhaust from aircraft engines mixes with cold air, causing water vapor to condense and freeze.

The persistence and appearance of contrails depend on atmospheric conditions, such as temperature, humidity, and altitude.

Despite the lack of credible evidence, the chemtrail mind control conspiracy theory persists, underscoring the importance of critical thinking, fact-checking, and relying on trustworthy sources when evaluating controversial claims.

By promoting evidence-based reasoning and healthy skepticism, we can help counter the spread of misinformation and encourage a more informed public discourse.

Image of an iguana for a blog post discussing famous conspiracy theories.
Some conspiracy theorists have claimed that powerful figures are
actually reptilian aliens in disguise, capable of shapeshifting into human form.

9. Reptilian Shapeshifters

The reptilian shape shifters conspiracy theory is one of the more bizarre and enduring famous conspiracy theories.

According to this theory, reptilian aliens from another planet are secretly controlling the world’s governments and institutions.

Proponents claim that these aliens have the ability to shape-shift into human form, allowing them to infiltrate powerful positions and manipulate global events.

Believers in this theory often point to supposed evidence, such as purported reptilian features of prominent figures and alleged witness accounts of shapeshifting.

However, there is no credible evidence to support the existence of reptilian shape shifters.

Psychologists suggest that belief in such theories may be driven by factors like the human tendency to find patterns in random events, the desire for simple explanations to complex problems, and the appeal of feeling privy to secret knowledge.

Ultimately, it is crucial to approach extraordinary claims with critical thinking and skepticism, relying on verifiable facts rather than unfounded conspiracy theories.

By promoting evidence-based reasoning, we can help foster a more informed and rational public discourse.

Image of the Denver International Airport in Denver, Colorado, U.S.
The Denver International Airport in Denver, Colorado, U.S.

10. Denver Airport Conspiracy

In our series on famous conspiracy theories, the Denver International Airport (DIA) stands out as a modern mystery.

Opened in 1995, DIA quickly became a hotbed of speculation due to its unusual features.

Conspiracy believers point to strange elements at the airport.

These include creepy murals with apocalyptic themes and odd symbols in the architecture.

Some claim there are secret underground bunkers or tunnels beneath DIA. Others link the airport to shadowy groups like the Illuminati.

Over time, these ideas spread online and through word-of-mouth.

Interestingly, the airport has embraced the rumors, using them in playful marketing campaigns.

However, there’s no real evidence for any sinister plots.

The artwork and design are just meant to be unique and thought-provoking.

While the theories are fun to ponder, DIA remains a normal, if quirky, airport serving millions of travelers each year.

Image of Paul McCarney in 1966, pictured with his Beatle bandmates.
Paul McCarney in 1966, pictured with his Beatle bandmates

11. The Paul McCartney Death Hoax

Among famous conspiracy theories, the “Paul is Dead” hoax stands out for its musical intrigue.

This theory claims Paul McCartney died in 1966 and was replaced by a look-alike.

It all started in 1969 when a college newspaper printed the rumor.

Believers point to “clues” in Beatles songs and album covers.

For example, they say, “Turn me on, dead man” is heard when playing “Revolution 9” backwards (link goes to YouTube).

Some think the Abbey Road cover shows a funeral procession.

The theory spread quickly through radio shows and magazines.

At first, the Beatles found it amusing.

Later, Paul got annoyed and denied it repeatedly.

Despite his ongoing music career, some still believe the theory today.

However, there’s no real evidence to support it.

Paul McCartney continues to perform and make music, proving he’s very much alive.

Image of a 1966 photo of a suspected UFO taken in Wanaque, New Jersey, U.S.
A 1966 photo of a suspected UFO taken in Wanaque, New Jersey, U.S.

Wrap-up: History’s Most Famous Conspiracy Theories

From the enduring mystery of the JFK assassination to the mind-bending theories about reptilian shapeshifters, we’ve explored some of the most captivating and controversial conspiracy theories in history.

While these theories may seem far-fetched or even entertaining, they reveal deeper truths about our society’s relationship with power, trust, and the search for meaning in a complex world.

By examining these famous conspiracy theories with a critical yet open mind, we can gain valuable insights into the human psyche and the forces that shape our beliefs.

So the next time you encounter a conspiracy theory, remember to approach it with a healthy dose of skepticism, a commitment to evidence-based thinking, and a willingness to engage in constructive dialogue.

Only by confronting these ideas head-on can we hope to build a more informed, empathetic, and truth-seeking society.

Image of two beams of light emanate from the 9/11 Memorial in downtown Manhattan for a blog post covering famous conspiracy theories.
Two beams of light emanate from the 9/11 Memorial in downtown Manhattan

FAQs: History’s Most Famous Conspiracy Theories

1. Why do people believe in conspiracy theories?

People believe in conspiracy theories for a variety of psychological, social, and cultural reasons.


One key factor is the desire for certainty and the need to make sense of complex, ambiguous, or random events.


Conspiracy theories offer a clear, structured narrative that provides a sense of order and control in a chaotic world.


They also appeal to the human tendency to perceive patterns and intentionality, even in unrelated or coincidental occurrences.


Additionally, believing in conspiracy theories can provide a sense of uniqueness and superiority, as individuals may feel that they possess special knowledge or insight that others lack.


Social factors, such as a distrust in authority, institutions, or official accounts, can also contribute to the appeal of conspiracy theories, particularly among marginalized or disenfranchised groups.


Furthermore, the social nature of conspiracy theories allows believers to form communities and share their ideas, reinforcing their beliefs through echo chambers and confirmation bias.


Finally, cultural factors, such as a society’s historical experiences, political climate, and media landscape, can create an environment that is more conducive to the spread and acceptance of conspiracy theories.




2. What are some common themes among famous conspiracy theories?

Many famous conspiracy theories share common themes and patterns.


One prevalent theme is the belief in a powerful, shadowy group secretly controlling events behind the scenes, such as the Illuminati, New World Order, or deep state.


Another common theme is the idea that governments or authorities are covering up important information, such as evidence of extraterrestrial life, secret technologies, or the true causes of significant events like 9/11 or the JFK assassination.


Conspiracy theories often involve the suppression or discrediting of dissenting voices, whistleblowers, or individuals who are believed to know the truth.


Many theories also incorporate elements of paranoia, suspicion, and mistrust of official accounts or mainstream media.


Some famous conspiracy theories revolve around the notion that commonly accepted explanations for events are merely a cover for more sinister or complex plots, such as the moon landing being faked or the Earth being flat.


Ultimately, famous conspiracy theories often provide an alternative narrative that challenges the status quo and appeals to those who are skeptical of authority or feel disenfranchised by societal power structures.




3. Are there any benefits to studying famous conspiracy theories?

Studying famous conspiracy theories can offer several benefits, both on an individual and societal level.


Firstly, examining these theories can help develop critical thinking skills by encouraging individuals to question information, evaluate evidence, and consider alternative perspectives.


This process can enhance media literacy and the ability to identify reliable sources, which is crucial in an era of widespread misinformation.


Secondly, analyzing the origins, spread, and impact of conspiracy theories can provide valuable insights into human psychology, social dynamics, and the factors that contribute to the belief in these theories.


This understanding can help develop strategies to combat the negative effects of misinformation and promote evidence-based thinking.


Thirdly, studying famous conspiracy theories can shed light on important historical, cultural, and political contexts, as these theories often reflect the anxieties, fears, and power dynamics of a given time and place.


By examining these theories, we can gain a deeper understanding of the complex forces that shape society and learn valuable lessons for navigating future challenges.


Finally, engaging with conspiracy theories in an academic or educational setting can provide a safe space for open dialogue, fostering empathy, understanding, and the ability to engage in constructive conversations across different beliefs and perspectives.




References: History’s Most Famous Conspiracy Theories

Barnes, Julian E. “Pentagon Review Finds No Evidence of Alien Cover-Up.” The New York Times, 8 Mar. 2024, www.nytimes.com/2024/03/08/us/politics/pentagon-ufo-alien-review.html.

Centers for Disease Control and Prevention. “Vaccines Do Not Cause Autism Concerns.” Centers for Disease Control and Prevention, 2020, www.cdc.gov/vaccinesafety/concerns/autism.html.

Coleman, Alistair . “Chemtrails: What’s the Truth behind the Conspiracy Theory?” BBC News, 22 July 2022, www.bbc.com/news/blogs-trending-62240071.

Davidson, Michael. “Vaccination as a Cause of Autism-Myths and Controversies.” Dialogues in Clinical Neuroscience, vol. 19, no. 4, Dec. 2017, pp. 403–407, www.ncbi.nlm.nih.gov/pmc/articles/PMC5789217/, https://doi.org/10.31887/DCNS.2017.19.4/mdavidson.

Graff, Garrett M. “The U.S. Government UFO Cover-up Is Real—but It’s Not What You Think.” The Atlantic, 17 Nov. 2023, www.theatlantic.com/ideas/archive/2023/11/us-government-ufo-uap-alien-cover-up/676032/.

Hernandez, Isabel. “Meet the Man Who Started the Illuminati.” History, 1 Nov. 2016, www.nationalgeographic.com/history/history-magazine/article/profile-adam-weishaupt-illuminati-secret-society.

Institute of Physics. “How Do We Know That We Went to the Moon?” How Do We Know That We Went to the Moon? | Institute of Physics, 2024, www.iop.org/explore-physics/moon/how-do-we-know-we-went-to-the-moon.

John F. Kennedy Presidential Library and Museum. “November 22, 1963: Death of the President | JFK Library.” Jfklibrary.org, JFK Library, www.jfklibrary.org/learn/about-jfk/jfk-in-history/november-22-1963-death-of-the-president.

Keith, David. “Chemtrails Conspiracy Theory.” Harvard.edu, 2019, keith.seas.harvard.edu/chemtrails-conspiracy-theory.

Kelly, Fred. “What Is the Illuminati Conspiracy Theory?” Theweek, 4 Feb. 2015, theweek.com/62399/what-is-the-illuminati-and-what-does-it-control.

Lindsay, James. “Seven Resources Debunking 9/11 Conspiracy Theories.” Council on Foreign Relations, 1 Sept. 2021, www.cfr.org/blog/seven-resources-debunking-911-conspiracy-theories.

“Lizard People, the Illuminati and the CIA: How Conspiracy Theories Thrive on Fear.” ABC News, 5 Oct. 2023, www.abc.net.au/news/2023-10-06/the-united-states-has-a-long-history-with-conspiracy-theories/102928506.

Mirsky, Steve. “Flat Earthers: What They Believe and Why.” Scientific American, 27 Mar. 2020, www.scientificamerican.com/podcast/episode/flat-earthers-what-they-believe-and-why/.

National Archives. “The President John F. Kennedy Assassination Records Collection.” National Archives, 29 Oct. 2018, www.archives.gov/research/jfk.

Pappas, Stephanie. “Are Flat-Earthers Being Serious?” Live Science, Live Science, 16 Dec. 2021, www.livescience.com/24310-flat-earth-belief.html.

Rains, Taylor. “I Got a Behind-The-Scenes Tour of the Conspiracy Theory-Filled Denver Airport to See Its “Secret” Tunnels and “Cursed” Horse.” Business Insider, www.businessinsider.com/denver-airport-conspiracy-theories-horse-gargoyle-behind-the-scenes-tour-2024-7. Accessed 18 July 2024.

Romano, Andrea. “The Most Popular Denver International Airport Conspiracy Theories.” Travel + Leisure, 13 Feb. 2020, www.travelandleisure.com/airlines-airports/denver-airport/denver-international-airport-conspiracy-theories.

Royal Museums Greenwich. “Moon Landing Conspiracy Theories, Debunked.” Royal Museums Greenwich, 2022, www.rmg.co.uk/stories/topics/moon-landing-conspiracy-theories-debunked.

Sardarizadeh, Shayan. “11 September 2001: The Conspiracy Theories Still Spreading after 20 Years.” BBC News, 10 Sept. 2021, www.bbc.com/news/58469600.

Sheffield, Rob. ““Paul Is Dead”: The Bizarre Story of Music’s Most Notorious Conspiracy Theory.” Rolling Stone, Rolling Stone, 11 Oct. 2019, www.rollingstone.com/music/music-features/paul-mccartney-is-dead-conspiracy-897189/.

Stuart Parramore, Lynn. “Like QAnon’s Capitol Rioters, the Nashville Bomber’s Lizard People Theory Is Deadly Serious.” NBC News, 12 Jan. 2021, www.nbcnews.com/think/opinion/qanon-s-capitol-rioters-nashville-bomber-s-lizard-people-theory-ncna1253819.

Tofel, Richard J. “Misinformation and the Saga of “Paul Is Dead.”” Columbia Journalism Review, 20 Dec. 2021, www.cjr.org/analysis/misinformation-paul-mccartney-dead.php.

Wenner Moyer, Melinda. “People Drawn to Conspiracy Theories Share a Cluster of Psychological Features.” Scientific American, vol. 320, no. 3, 1 Mar. 2019, www.scientificamerican.com/article/people-drawn-to-conspiracy-theories-share-a-cluster-of-psychological-features/, https://doi.org/10.1038/scientificamerican0319-58.