1. The wand lore
The symbolism of the material from which the characters’ wands are made has its roots in the Celtic calendar and lore, picked by Rowling according to the characters’ birthdays.
Harry’s wand, made of Holly, is symbolically connected to the character of Harry himself, as Celtic astrology describes this sign as an affectionate, but skilled and confident (sometimes overly-confident) leader. Holly was also believed to repel lightning, which has a connection with Harry’s lightning-shaped scar, given to him by a twin wand made of Yew, whose properties are a contrast to Holly. (Yew is a symbol of longevity, which, after all, was what Voldemort was after).
Ron’s two wands both had a unicorn hair core, but he inherited the first from Charlie, his brother. The second wand was made of Willow, which is also one of the Celtic traditional woods, and according to Celtic astrology, people born in the Willow sign are the observers who have a tendency to hold themselves back.
Hermione's wand, with a core made of dragon’s heartstring, is made of vine wood, whose symbol, the spiral, has the properties of consciousness and development, and the vine wood stands for adjustment and sacred knowledge. As for astrology, those born in the Vine sign are good at empathizing with others and are “connoisseurs of refinement”.
2. What the first book foreshadowed
Near the end of Philosopher’s Stone, Harry, Ron and Hermione go through seven obstacles while trying to retrieve the stone. Each of these obstacles may be interpreted as a foreshadowing for the corresponding book.
- Philosopher’s Stone – the trap door, guarded by Fluffy, is the first obstacle, set by Hagrid, who has a lot of the focus of the first book on him as he is the one who breaks it to Harry that he is a wizard, and the trio spend a lot of time with him, revealing the subplot with the baby dragon and Fluffy. Also, the trapdoor could be interpreted as a symbol of an opening, which in relation to the first book corresponds as the beginning of Harry’s time at Hogwarts.
- Chamber of Secrets -The Devil's Snare, which is a deadly plant, was placed as a second obstacle by Professor Sprout, who plays a more important role in the second book as she is the one who grows mandrakes which break the spell of Bazilisk’s petrifying gaze. The Devil’s Snare can also be a symbol for the Bazilisk itself, as it doesn’t like fire, and Dumbledore’s phoenix Fawkes played a vital role in defeating it. And also, it could be said that in both instances there was a Weasley set free by fire.
- Prisoner of Azkaban – the flying key room symbolizes a book that has a lot of subplots involving flying. There is the subplot involving Harry’s brooms: how he lost his Nimbus 2000 and eventually replaced it with a Firebolt, the most coveted broom of that period. Every Quidditch match is described in detail, which is not the case in any other book of the series. Finally, there is the important subplot involving the hippogriff Buckbeak, without whose flying the ending of the book would have to be quite different.
As for the symbolism, the third obstacle was the only one that was not potentially lethal, and the third book is the only one that doesn’t feature Voldemort.
- Goblet of Fire – the chess game, fourth obstacle, corresponds well with the overall theme of the fourth book, as it is a game, and a fairly lethal one. Harry, Ron and Hermione replace three figures in the chess game, which is a number that appears in the name of the competition as well: The Triwizard Tournament. Finally, for the first time one of the trio gets harmed, as Ron gets knocked unconscious, and this foreshadows the first death of the series in the fourth book.
- Order of Phoenix – the troll, Quirrell’s trap, could essentially be considered as one set by Voldemort, as Voldemort possessed Quirrell’s body. This aligns well with the main plot of the fifth book, where Voldemort lures Harry into the Department of Mysteries to find a prophecy concerning him and Voldemort.
- Half-Blood Prince – the potion logic puzzle fits perfectly with the sixth book’s focus upon the world of potions. A new character, new Potions Professor is introduced at the very beginning, and he is the important point in quite a few instances in the main plot. Also, the old Potions master, Snape, is revealed as the Half-Blood Prince. This is the book where Harry learns about Voldemort’s seven horcruxes, and in the puzzle, there are seven potions. Three of these potions are poisonous, and three people die trying to destroy the horcruxes.
- Deathly Hallows – the Mirror of Erised, an obstacle set by Dumbledore, shows the deepest desire of the one who looks into it. In the last book, Harry learns a lot about Dumbledore’s past and who he really was, and his guidance, both through the mirror in the first book, as in the last, proves instrumental in helping Harry defeat Voldemort, and in both cases Harry confronts his arch nemesis alone.
3. Code names and alternate titles
By the time the Harry Potter series was becoming big, code names for the manuscripts were necessary to help keep the book under the radar. Among the code names were spurious titles such as Edinburgh Potmakers, andThe Life and Times of Clara Rose Lovett.
The Triwizard Tournament was supposed to have another name - The Doomspell Tournament, but the change was suggested to Rowling during March 2000.
Also, a suggested name for the American edition of Harry Potter and the Philosopher’s Stone was Harry Potter and the School of Magic, but Rowling did not feel like this title would fit and suggested that they call it the Sorcerer’s Stone, which felt less “arcane” than the original title.
4. Inspiration for the adult editions
A staff member of Bloomsburysaid that, on his commute,he had seen a man reading the book, hiding it behind a copy of The Economist.After this anecdote made its way into the press, the Bloomsbury representatives decided to actually produce an adult edition of Harry Potter, with photographs instead of illustrations.
The first edition was published in September 1998, and on the cover it featured a photo of an American steam locomotive.
5. Harry Potter could have had a glossary
During the editing of Chamber of Secrets it was suggested that there should be a glossary at the end of the book, containing information and history for people who hadn’t read Philosopher’s Stone.
Even though the idea was abandoned back then, the need for an encyclopedia of some sort has been recognized by many, and Rowling has since won a court case against RDR Books over their plans to publish the Harry Potter Lexicon. As of 2012, Rowling has stated that she was working on a Harry Potter Encyclopedia.
6. Was Professor Trelawney often right?
During the Christmas dinner at Hogwarts in Prisoner of Azkaban, Professor Trelawney is asked to join a table with twelve other characters by Dumbledore. She initially refuses, citing a superstition that if thirteen people dine at the same table, the first one to stand up will also be the first one to die.Later in the evening, Harry and Ron left the table simultaneously, however on a later instance, (and a later book,Order of the Phoenix),Sirius shares a table with twelve other members of the Order, and is the first to leave it (and the world of the living, too).
Also, during a Divination class, Professor Trelawney attempted to guess when Harry was born, saying, wrongly, that it was midwinter. However, it’s possible that she might have just felt Voldemort’s presence in Harry (as Harry was his horcrux), because Voldemort’s birthday is December 31st.
7. The theory of the Three Brothers and Death
This is the one of the most recent theories and has been confirmed by Rowling herself, who said in a tweet that it “fits” – the story about the three brothers and Death, from Deathly Hallows, is an allegory about the Harry Potter characters.
The first brother, who got the Elder Wand from Death, died for power. He represents Voldemort, who also sought the Elder Wand and died in the same way.
The second brother, who got the resurrection stone from Death, died for his lost love. A parallel can be drawn with Snape, whose love for Lilly Potter shaped his actions and who died protecting her son.
The third brother wanted a way to hide from Death, and Death gave him the Invisibility cloak, so that, when the time for his passing came, he greeted Death like an old friend. This is of course Harry, as the Invisibility cloak was his family’s heirloom and he greeted Death much in the same way. How do we know that?
Because Death is Dumbledore, who had all the Hallows in his possession – he was the master of the Elder Wand, he got the Invisibility cloak from James Potter and he passed it down to Harry, and he got the resurrection stone from Voldemort’s ring horcrux (also a family heirloom, which suggests Voldemort and Harry are distant relatives).
And, when Harry was killed by Voldemort (Voldemort thus destroying his own horcrux), he woke up at King’s Cross Station, where he was greeted by Dumbledore.