Since just after the assassination of John F. Kennedy, conspiracy theories about what and who were really behind the assassination have been abundant. Some theories are barely plausible, but others seem to fill in the gaps left by the Warren Report, which was the official government report about the JFK assassination and which was created by the Warren Commission set up by President Johnson.

Even if you aren't that into conspiracy theories, it can be interesting to check out the top five theories about the assassination of John F. Kennedy. The following five theories are the ones that have gained the most traction with novelists, historians, and conspiracy theoreticians over the years.

1. Jack Anderson's Cuban Theory
One somewhat plausible theory that was proposed by Jack Anderson, a newspaper columnist, is that Kennedy was killed either by right-wing Cubans who felt betrayed by the President who didn't let US forces participate in the Bay of Pigs invasion or that he was killed by Fidel Castro's operatives. Apparently, Castro may have just been taking revenge for multiple attempts on his life that were made by CIA or Mafia contacts. The biggest problem with this theory is that by the 1960's, the community of Cuban exiles was already infiltrated heavily by CIA operatives, so it seems unlikely that such a plot could have gone down without prior knowledge on the part of US intelligence agencies.

Why would the Soviets have wanted to kill JFK when the premier, Kruschev, couldn't have gotten better treatment from Kennedy's potential successors than he had from Kennedy himself?
2. The KGB
This theory is also called the Reader's Digest Theory, and it is the one that right-wing theorists most often lean toward. Lee Harvey Oswald's family had traceable contacts to the KGB, so it seems feasible that Oswald was actually a KGB operative send to kill Kennedy during the worst part of the Cold War. This theory also integrates the fact that the Warren Commission covered up the real explanation for the assassination, since President Johnson would not have wanted to start World War III over the death of JFK. Of course, the major problem here is motive. Why would the Soviets have wanted to kill JFK when the premier, Kruschev, couldn't have gotten better treatment from Kennedy's potential successors than he had from Kennedy himself?

3. The Mafia
Another popular theory for the JFK assassination looks more closely at the Kennedy family's personal politics, which were very anti-organized crime. It's known very clearly that the Mafia boss Jimmy Hoffa was an enemy of Robert Kennedy, JFK's brother and Attorney General. Besides this, the Mafia was linked heavily to Cuba and had lots of money riding on the Castro revolution. While this theory is plausible, it fails to explain how the Mafia would have involved the Warren Commission in the cover-up or why they wouldn't have had a slew of killings as they got rid of everyone involved in the assassination of the American president.

4. US Government
Many conspiracy theorists like this particular theory best because it's interesting and because it actually does tie up nearly all the loose ends. One explanation as to why the government, or at least a faction of the government, decided to assassinate the President is that the CIA was angry with Kennedy for giving away Cuba, was afraid he would also give away Vietnam, and/or was angry about the high-level firing rampage Kennedy went on after the Bay of Pigs incident. Clearly, an assassination that started within the CIA would be easy for CIA operatives to cover up during the Warren Commission's reporting process.

5. The Zero Theory
One far-fetched theory links the JFK assassination with other assassinations of presidents elected in a year ending with zero. Looking at history, every president elected in a zero-ending year, except for Ronald Reagan, has died in office, and Reagan very nearly did die in office. Those who fall in with this theory have many different explanations as to who is behind the so-called Zero Game, including the Freemasons, the Vatican, and even the British royals.
Who Really Killed JFK?

The truth is that many, many people believe the JFK assassination was much more complex than a crazed Lee Harvey Oswald acting on his own and just happening to be killed by Jack Ruby. Jamie Scott from CreditDonkey says, We may never really know who actually killed JFK, as evidence just doesn't stack up one way or another to fully prove one assassination theory. Truly, though, it's interesting to at least look at different theories to see what they have to say about who might have killed President John F. Kennedy.