1. Ron Weasley is actually a time-travelling Dumbledore
This has been a popular theory since 2004. It’s based on the idea that the chess game in Harry Potter and the Philosopher’s Stone is an allegory for the series as a whole. Ron plays the knight and then the king – just like Dumbledore does in the larger war. There’s also the fact that they "look similar", they’re both described as tall and thin with a long nose, and they both have auburn hair (or Dumbledore did before it went white).
There’s also the fact they have similar characteristics, such as loving Bertie Bott’s Every Flavour Beans. Far fetched? Yes, but not unbelievable.
2. The Dursleys were under the effect of a horcrux
For years we thought the Dursleys were simply evil - but according to one Tumblr theory the Dursleys were influenced by dark forces. Remember in the last Harry Potter when Ron turns really horrible because of about 5 minutes of exposure to a horcrux? Well, the Dursleys were exposed to Harry Potter - who is a horcrux - for 10 years.
3. The Deathly Hallows is symbolic of all the books
According to this Tumblr post about the final fight scene in the Deathly Hallows, Ron and Hermione are chased by an ugly creature and then hide behind a bike (like in the first book), then attacked by spiders (like in the second book), then a werewolf appears (like in the third book), and then dementors appear (like the fourth book), then the Order of the Phoenix appears, as happens in book five, and then they reach Snape who is the half-blood prince. This is one of the most convincing one’s we’ve read.
4. Horcruxes were created by cannibalism
JK Rowling never revealed exactly how Voldemort managed to split his soul into seven pieces and evade death. Reddit user, sirione13 theorised that he did it by eating his victims. She argues that cannibalism throughout history has been associated with gaining strength, and the only way to make a horcrux is through murder – yet Voldemort wasn’t responsible for all of the deaths that created horcruxes.
5. Harry is now immortal, and that’s awful
Probably the saddest Harry Potter fan theory was posted by this Imgur user. The Harry Potter books say “either must die at the hand of the other for neither can live while the other survives” most interpreted this to mean that one had to kill another (as Harry kills Voldemort in the last book).
This theory questions that premise and asks if it really means the only way that either of them could die was at the hands of the other. Hence by killing Voldemort, Harry forfeits his death – the ultimate sacrifice for Harry, as it means he’ll never be reunited with his deceased friends and family.
6. J.K. Rowling is really Rita Skeeter
This is our personal favourite. The theory goes Rita was banished from living in the magical world after it was discovered that so much of her work was fabricated.
She then went to live with the Muggles, and fell upon difficult times, so turned to writing in an effort to make a living for herself. This would mean Harry Potter is 100% true, which makes sense to us, no-one has that big of an imagination.
7. Draco Malfoy is a werewolf
This theory argues that Draco exhibits all the signs of a werewolf, often described as pale and looking ill, he doesn’t give in his transfiguration homework and he missed out a Quidditch match against Gryffindor.
8. Muggles already won a war with wizards
Last year, Reddit user celeritas365 theorised that there had already been a great war between wizards and Muggles, and the Mmuggles won. This theory has a lot of merit. In the fourth book, the Minister of Magic is required to tell the Prime Minister that he was bringing dangerous magical creatures into the UK - an odd rule for wizards to make up, as they usually hide things from Muggles. She goes to the theorise that the very fact it’s referred to as a ‘ministry’ makes it sound more like a government department than a government in itself.
9. The Defence against the Dark Arts teaching position is cursed
The most predictable thing about the Harry Potter series was that each Defence against the Dark Arts teacher would only last a year. This was because the position was cursed by Tom Riddle (Voldemort) when he was refused the position. Dumbledore knew this, and hence refused Snape the job to stop him from rendering him useless, and therefore no longer being a spy.
10. Arthur Weasley was unknowingly under the Imperius curse
This theory speculates that there were a number of wizards placed under the imperius curse, which meant Voldemort had complete control of their actions. It explains why he did not rise further in the Ministry of Magic, as well as some of the skeletons in the Weasley closest.
11. The Harry Potter trio are only in Gryffindor because they asked
This Tumblr theory argues that Ron, Harry and Hermione should really be in Hufflepuff, Slytherin, and Ravenclaw respectively, but ended up in Gryffindor because they had the courage to ask.