Quantos anos tem o quidditch?

_{A resposta de Jason Baker responde bem aos escritos extensos de Rowling, mas o OP declarou preferência por informações encontradas na própria série principal.}

A mais antiga referência específica de Quadribol na série principal é a Copa do Mundo de 1473, mas o próprio Quadridol teria que ser mais antigo que isso.

Harry learned that there were seven hundred ways of committing a Quidditch foul and that all of them had happened during a World Cup match in 1473; that Seekers were usually the smallest and fastest players, and that most serious Quidditch accidents seemed to happen to them; that although people rarely died playing Quidditch, referees had been known to vanish and turn up months later in the Sahara Desert.
_{Harry Potter and the Philosopher's Stone - Chapter 11}

Note que se todas as 700 faltas de Quadribol já tivessem sido codificadas, pareceria que o próprio Quadribol era muito mais antigo.

Há também uma referência possivelmente mais antiga em Cálice de Fogo sobre o número da copa do mundo.

“Ladies and gentlemen . . . welcome! Welcome to the final of the four hundred and twenty-second Quidditch World Cup!”
_{Harry Potter and the Goblet of Fire - Chapter 8}

Parece estar implícito que as Copas do Mundo foram realizadas a cada quatro anos no momento em que os livros acontecem (fazendo o primeiro caminho de volta em 310), mas para que eles tenham sido um torneio em 1473 deve nem sempre ter sido o caso. Ou é apenas matemática de Rowling novamente.

Há um livro inteiro (fora do universo e também no universo) sobre esse assunto: Quadribol através dos tempos .

De acordo com este livro, o primeiro jogo do que poderia ser reconhecido como quadribol foi jogado no século XI; algumas entradas em um diário do período descrevem alguns elementos reconhecíveis:

Tuesday. Hot. That lot from across the marsh have been at it again. Playing a stupid game on their broomsticks. A big leather ball landed in my cabbages. I hexed the man who came for it. I'd like to see him fly with his knees on back to front, the great hairy hog.

Tuesday. Wet. Was out on the marsh picking nettles. Broomstick idiots playing again. Watched for a bit from behind a rock. They've got a new ball. Throwing it to each other and trying to stick it in trees at either end of the marsh. Pointless rubbish.

Tuesday. Windy. Gwenog came for nettle tea, then invited me out for a treat. Ended up watching those numbskulls playing their game on the marsh. That big Scottish warlock from up the hill was there. Now they've got two big, heavy rocks flying around trying to knock them all off their brooms. Unfortunately didn't happen while I was watching. Gwenog told me she often played herself. Went home in disgust.

^{Quidditch Through the Ages Chapter 3: "The Game from Queerditch Marsh"}

O último elemento reconhecível, o pomo de ouro (originalmente um animal vivo, chamado de Snidget), era originalmente parte de um esporte diferente do mesmo período:

From the early 1100s, Snidget-hunting had been popular among many witches and wizards.

[...]

The diminutive size of the Snidget, coupled with its remarkable agility in the air and talent at avoiding predators, merely added to the prestige of wizards who caught them. A twelfth-century tapestry preserved in the Museum of Quidditch shows a group setting out to catch a Snidget. In the first portion of the tapestry, some hunters carry nets, others use wands, and still others attempt to catch the Snidget with their bare hands.

^{Quidditch Through the Ages Chapter 4: "The Arrival of the Golden Snitch"}

O livro continua descrevendo como os dois esportes se encaixaram:

Snidget-hunting finally crossed paths with Quidditch in 1269 at a game attended by the Chief of the Wizards' Council himself, Barberus Bragge. We know this because of the eyewitness account sent by Madam Modesty Rabnott of Kent to her sister Prudence in Aberdeen (this letter is also on display in the Museum of Quidditch). According to Madam Rabnott, Bragge brought a caged Snidget to the match and told the assembled players that he would award one hundred and fifty Galleons to the player who caught it during the course of the game.

^{Quidditch Through the Ages Chapter 4: "The Arrival of the Golden Snitch"}