However, it took until the last couple of books before anyone realised that the real hero of the series was in fact not Harry, but Neville Longbottom.
Other people on the internet have obviously said it before but it bears repeating: Neville could have, no should have, been the Chosen One. The prophecy given by Professor Sybil Trelawney foretold of a child born in July who grow up to would defeat He Who Must Not Be Named (It's Voldemort, guys, his name is Voldemort).
|What sane individual wouldn't trust a prophecy made by this person?|
That prophecy stipulated that the child would be born of parents who had thrice defied Voldemort and would be the one to defeat him. Furthermore, the Dark Lord would mark him as an equal but the child have a power that Dark Lord wouldn't (spoiler: it's love. The Power of Love or Friendship or whatever). However, Severus Snape, who overheard the prophecy, only heard the first part and not the bit about marking the child as an equal and extra powers which might have been useful for Voldemort to know.
|Da-da, da, da, daaa- aah. That's so Snape.|
However, in his mad rush to kill a defenseless infant who would grow up to have terrible vision, Voldemort did not consider killing a defenseless infant who would grow up to have terrible tastes in pets (toads are horrible pets, end of discussion). This turned out be a unwittingly good move on Voldemort's part since Neville would probably have ended him.
For most of the series, Neville is clumsy, bumbling and incompetent, unable to work the most basic of spells or do anything much of use at all really. However, this is only because he never had the motivation to do so and is emotionally crippled due to the fact both his parents are completely insane and institutionalized. Dealing with the stress of having both his parents mentally broken had its affect on Neville and we can see this through his timidness and lack of confidence for most of the series. But once Neville has something that can motivate him, he metamorphoses into a badass of smoldering bravery and ass-kickery.
|You better be patting me on the back or that is the last time you see that hand.|
We can see this right in the beginning when Neville stands up to Harry, Ron and Hermonine when they are sneaking out of Gryffindor tower to prevent the Philosopher's stone being stolen. His devotion to his school house and willingness to stand up to his friends for what he thinks is right, wins Gryffindor the House Cup for the first time in ages as Dumbledore awards him the 10 points they needed to defeat Slytherin.
|I did what now?|
However, it is once Neville learns that Bellatrix Lestrange, the person responsible for torturing his parents into insanity, escaped from Azkaban that he really steps up his game and shrugs off his losery clumsiness. He works harder than anyone else at the Order of the Phoenix, improving and honing his skills in order to avenge his parents. But that is not his path. While he does face Bellatrix several times in battle, Neville's true badassery comes not through revenge, but revolution.
|Just to be clear, that mass of people behind him are his followers.|
When Harry doesn't return to Hogwarts, opting instead to go treasure hunting and camping or whatever, towards the end of the series, Neville steps up to lead the rebellion against Voldemort's Death Eaters who are running the school. That is, Neville organises, and serves as a symbol of inspiration for, a bunch of scared school-kids against known killers and terrorists. Just because he can.
|The kids in the back are like, "Holy shit, Neville just stood up to a Death Eater... Literally. He just stood up."|
With a sense of purpose and motivation, Neville becomes the badass no one expected he could ever be. This leads him to use a sword in a wand fight, because fuck it, he's Neville Longbottom and shooting spells is too easy.
|He also kills a really big snake with it. No, seriously, it was a really big snake. And like, deadly poisonous.|
That's around about the time, the Dark Lord Voldemort, the most powerful and evil wizard alive, wielding the Elder wand, the most powerful wand ever, the man who instilled so much fear in the wizarding world that they \were too scared to say his name aloud, asks Neville to surrender. Instead, of cowering like any normal person, Neville delivers an emotionally rousing speech about friendship and stuff before politely declining Voldemort's request by killing his pet snake.
|You got something to say, punk?|
This gives Harry the chance to stop pretending to be dead or whatever and have a final fireworks battle with Voldemort, who is distraught at the death of his snake and the fact Harry was only pretend-dead and not real dead. Harry might have won the battle with Voldemort but it's only because of Neville.
|Neville is as gentle and caring a lover as he is hardcore and heroic a sword-wielding snake-killing badass.|
All this is just to prove that if Voldemort had decided to kill Neville instead of Harry then,
Correction: In the original version of this post, I stated Wormtail overheard the prophecy. However, this was pointed out to me to be incorrect. It was in fact, Severus Snape. So I amended it.
I can admit that I was wrong. I was wrong. See? Told you I could do it.