The Harry Potter series starts out squarely in the genre of children's literature. Harry is eleven, and so is his intended audience. By the time we get to Goblet of Fire, we seem to be inching towards young adult territory. Not only are there some PG hints of dating and hormones, but also there are eight murders (if you include Barty Crouch, Jr. getting his soul eaten by a Dementor, which we do). What's more, the book is long enough to put off a lot of younger kids. Still, the language is plain and straightforward and the cover illustrations seem marketed towards a younger audience. We're going to stick with the genre of children's literature for Goblet of Fire. It's a tale of witchcraft and enchantment, so Goblet of Fire is also a fantasy series. And one of the central themes of Goblet of Fire is Harry's growth and development, so it is clearly a coming-of-age novel.
Amelia Bedelia and the Cat. Indiana Jones and the Last Crusade. And Harry Potter and the Goblet of Fire. What do these titles have in common? Well, for starters, they all belong to popular series that focuses on a single character. When you want your character to become a brand name known all over the world, what better way than to put his or her name right up there in the title? That way, all you have to do is look at the book cover to realize that you're reading one of the Harry Potter books. Clearly done, Ms. Rowling.
As for the "Goblet of Fire" part of the title, when Rowling went on her first book tour for the fourth Harry Potter novel, she commented:
I changed my mind twice on what it was. The working title had got out – "Harry Potter and the Doomspell Tournament." Then I changed Doomspell to Triwizard Tournament. Then I was teetering between Goblet of Fire and Triwizard Tournament. In the end, I preferred Goblet of Fire because it's got that kind of "cup of destiny" feel about it, which is the theme of the book. (source)
So the title choice is a mix of publicity and artistic considerations. The original name got leaked to the press, so Rowling felt she had to choose something else. And she changed it to a name she liked better anyway, something with that "cup of destiny" feel – the Goblet of Fire. The Goblet of Fire sounds like something magical and mysterious – something we want to find out more about, right? (Something we don't want to drink from, right?) So put "Goblet of Fire" in the same title with "Harry Potter" and we just have to read this book!
Any book in a series (except maybe the last one) has to walk a delicate balance. It must wrap up the individual plot of one book while still leaving enough loose ends to carry on in the next one. And we think J.K. Rowling balances both of these demands absolutely beautifully in Harry Potter and the Goblet of Fire.
The major plot arcs of the book – the Triwizard Tournament, Harry's dreams about Voldemort, the extremely awkward onset of puberty, and the horrible Rita Skeeter – all get some kind of resolution in the last chapter. First, the Triwizard Tournament: by the last chapter, we know that Barty Crouch, Jr. has engineered this whole Harry-Potter-in-the-Triwizard-Tournament thing to help bring Voldemort back to life. And we know that Voldemort murdered poor Cedric Diggory. Professor Dumbledore links these events – the Triwizard Tournament, Voldemort, Harry Potter, and Cedric Diggory – officially and publicly at the Leaving Feast. He literally gets the last word on the Triwizard Tournament.
The return of Voldemort explains why Harry's scar has been aching so much during the year: as Voldemort has been growing more powerful, his magical link to Harry has been acting up. Harry's scar pain at the beginning of Goblet of Fire foreshadows what happens at the end: the dramatic return of Voldemort as a serious threat to the wizarding world once again.
As for the arrival of love (and thus puberty) at Hogwarts, Harry's major crush on Cho Chang has been short-circuited by her brief relationship with Cedric Diggory. At the Leaving Feast in the last chapter, we see "tears pouring silently down her face" (37.46). So Harry's first real experiment in love is not going so well, we'd say.
And, last but not least, there's the plot thread of Rita Skeeter. Hermione figures out (quite brilliantly, we might add) that Rita Skeeter has been getting all of her news by spying on private conversations while she's in the form of a beetle. So Hermione captures the law-breaking journalist in a jar and blackmails her into promising not to write anything nasty about other people for a whole year.
So, by the end of Goblet of Fire, the Triwizard Tournament has come and gone, Voldemort (who has been threatening to reappear for three years) is finally back, Harry has embarked on the romantic agonies of being a teenager, and Rita Skeeter is unable to print any more lies for a year, on pain of being turned in to the Ministry of Magic for being an unlicensed Animagus (someone who can change into an animal).
Yet, we're still left with a huge number of questions. Voldemort has risen again: so what? What's he going to do next to reestablish his reign of terror? Harry's relationship with Cho Chang seems to have ended before it started – but is that really the last we'll see of Cho? Will Harry fall for another girl? And how about the simmering tension between Hermione and Ron? Hagrid has been sent on a secret mission – to where? These questions are probably why J.K. Rowling calls the last chapter of the novel "The Beginning." It might be the final part of The Goblet of Fire, sure, but it's the beginning of Harry's all-out war against Voldemort (and the beginning of his budding relationships with girls, let's not forget).
As J.K. Rowling said in an interview on the day Harry Potter and the Goblet of Fire was released worldwide,
The fourth is a very, very important book. Well, you know because you read it, something incredibly important happens in book four and also it's literally a central book, it's almost the heart of the series, and it's pivotal.(source)
This is what we think is so amazing about Goblet of Fire: it's a "central" book. It marks the end of Harry's childhood, as he starts falling in love and taking on new responsibilities – meaning, he's fighting the Dark Lord, not just taking out the trash or mowing the lawn. It also marks the beginning of the next wizarding war against Voldemort (whether Cornelius Fudge will admit it or not). It's at the heart of the series and whenever we reread it, we're always amazed again by how much Rowling accomplishes in it.
The setting that we really care about in Harry Potter is, of course, Hogwarts School for Witchcraft and Wizardry. Little Hangleton is only significant because the Riddle family once lived there; it's not very distinctive otherwise. And Privet Drive is nightmarishly normal and Mugglish. Even the Dursleys' fireplace runs on electricity. There's nothing fantastic about their home at all.
By contrast, Hogwarts Castle – which is only accessible through a magic train we Muggles can't even see – is filled to the brim with giant squid, trick staircases, Hungarian Horntails, and Forbidden Forests. Every corner of the castle seems to have some new enchantment to discover. It's like a dream come true for everyone who has ever been bored with humdrum Muggle life or school.
But along with the living portraits and Quidditch pitches comes real danger and emotional agony. Just because the magic world is cool to read about doesn't mean that it would be safe or pleasant to live there. A lot of social problems that we endure in our lives persist in the wizarding world, including poverty, racism, and terrorism. J.K. Rowling sums up:
Harry entered this world that a lot of us would fantasize would be wonderful: "I've got a magic wand and everything will be fabulous" – and the point being that human nature is human nature, whatever special power and talents you have [… Harry] walks into this amazing world, and it is amazing, and he immediately encounters all the problems you think he would have left behind and they are in an even more extravagant form because everything is exacerbated by magic. (source)
In the first chapter, Frank Bryce, the unfortunate gardener for the Riddle house, is arrested for the murder of the Riddle family in Little Hangleton, England. Frank is soon released because there's zero physical evidence to show how the Riddles were murdered. Although Frank claims to have seen a teenage boy murder the Riddles, no one believes him. In fact, the villagers are absolutely against Frank. Even though no one officially accuses him of anything, everyone seems to agree with village resident Dot when she comments, "So far as I'm concerned, he killed them, and I don't care what the police say" (1.23). So Frank has been convicted of murder according to public opinion, even if there's no real evidence against him.
This is why we find the name of the village pub, the Hanged Man, to be significant. A hanged man is (generally) a man who has been convicted and executed of a crime. It's in the Hanged Man pub where all of these unfounded rumors against Frank Bryce start circulating, so the name of this pub foreshadows what Frank Bryce is. Oh, he hasn't been executed (at least, not until later on in Chapter 1), but he has definitely been convicted, if only unofficially in the minds of all the villagers.
Harry's lightning bolt-shaped scar on his forehead becomes a major plot point in Harry Potter and the Goblet of Fire. The scar is the only mark on Harry's body from when Voldemort tried to kill him with an Avada Kedavra curse when he was a baby. It's also always been a way for strangers to identify Harry, whether he wants to be recognized or not.
But now, it's more than just proof of what happened to Harry thirteen years before – it's a tangible symbol of Harry's magical connection to Voldemort. The horrible pain that Harry feels when Voldemort casts the Cruciatus Curse is concentrated right on this scar. And his dreams of Voldemort's activities also cause his scar to ache. Professor Dumbledore puts forward a theory, and we trust his word:
It is my belief that your scar hurts both when Lord Voldemort is near you, and when he is feeling a particularly strong surge of hatred [...] Because you and he are connected by the curse that failed [...] That is no ordinary scar. (30.164-6)
We know that Ron is afraid of spiders – we find out when Harry and Ron head out to the Forbidden Forest in Harry Potter and the Chamber of Secrets and meet a giant spider (hey, anyone would be afraid of that). When Professor Moody brings out his jar of three spiders to demonstrate the Unforgivable Curses, Ron is frightened even before Professor Moody demonstrates the curses. So, in this scene, the spiders are a symbol of fear; they underline how terrifying these curses are by their very nature.
"Goblet of Fire" just sounds cool; who wouldn't want to see a goblet of fire? For more on the origin of this name, check out "What's Up With the Title?" The Triwizard Cup is the goal for which Harry is competing. It symbolizes his reward for all the struggle and hardship he has endured as the youngest unintended champion in the Tournament.
What's interesting about both the Goblet of Fire and the Triwizard Cup is that both of them are smokescreens. They seem like they should be important in and of themselves – their names are capitalized, after all. But their primary significance is what they lead to: the Goblet of Fire is enchanted into choosing Harry as a Triwizard Tournament competitor, and the Triwizard Cup becomes a Portkey to bring Harry and Cedric to the Little Hangleton graveyard where Voldemort is waiting. These two objects are red herrings, things that look like clues but really aren't. You can easily forget about the Goblet of Fire by the end of Chapter 16. It's a means to an end, as is the Triwizard Cup.
We know from Book 1 that Harry and Voldemort's wands share the same core – phoenix feather. (In Goblet of Fire, we find out that the phoenix in question is Dumbledore's dear Fawkes.) The shared wand core has huge plot significance in Goblet of Fire, since that's what triggers the Priori Incantatem effect that allows Harry to get away from Voldemort. It's also symbolically significant in the same way Harry's curse scar is: Voldemort and Harry are linked by their magic. That's how we know that Voldemort is going to keep coming up as part of Harry's destiny, no matter how many times Harry escapes or delays their inevitable showdown. What's more, phoenixes are known for coming back to life even when everything seems lost. This is something that both Harry and Voldemort (regrettably) have proved able to do.
In general, wand cores say something about the personality of the wizard or witch who carries it. Fleur Delacour's wand uses hair from her veela grandmother's head. Mr. Ollivander comments that veela hair "makes for rather temperamental wands" (18.172). And Fleur is pretty darn temperamental herself, with her 180-degree turnaround on what she thinks of Harry. Cedric's wand comes from the tail hair of "a particularly fine male unicorn" (18.176), and Cedric is a particularly fine young man. All the associations with unicorns are good: they're brave and pure of spirit. Cedric seems to share those qualities. Last but not least, Viktor Krum's wand contains dragon heartstring and is "quite rigid" (18.183). He is also stiff, awkward, and somewhat dangerous, but he's brave and strong, a lot like a dragon.
By Goblet of Fire, we don't really know why the Dursleys insist on giving Harry Christmas presents – they might as well save themselves the effort. In Book 4, they hit "an all-time low" by giving Harry "a single tissue" (23.49). The simple fact that the Dursleys bother to send Harry a single tissue, rather than just ignoring him entirely over Christmas, suggests that their gift-giving is meaningful. We just don't know what it symbolizes yet. We'll just have to keep reading the series to find out!
There are no direct references to other novels in Harry Potter and the Goblet of Fire, although J.K. Rowling has mentioned reading (among others) Enid Blyton, Paul Gallico, and Elizabeth Goudge as a child (source). She also likes Jacqueline Wilson, David Almond, Aidan Chambers, Henrietta Branford, and Philip Pullman (source).