How old is quidditch?

Question

We know that quidditch is at least decades old, but how long ago did witches and wizards start playing the sport? Out of universe, I would imagine hundreds of years at least as the image of witches on brooms is a very old one. I'm curious, though, what the earliest references to quidditch are in the books or movies.

Answer 1

_{Jason Baker's answer does a good job of answering from Rowling's extended writings, but the OP has stated a preference for information found in the main series itself.}

The earliest specific Quidditch reference in the main series is to the World Cup of 1473, but Quidditch itself would have to be older than that.

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 that if all 700 Quidditch fouls had already been codified, it would seem that Quidditch itself was much older.

There is also a possibly older reference in Goblet of Fire concerning the number of the world cup.

“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}

It seems to be implied that the World Cups were held every four years at the time that the books take place (making the first one way back in 310), but it in order for their to have been a tournament in 1473 this must have not always been the case. Or it's just Rowling maths again.

Answer 2

There's a whole (out-of-universe, and also in-universe) book on this subject: Quidditch Through the Ages.

According to this book, the first game of what might be recognized as quidditch was played in the 11th century; some entries in a diary of the period describe some recognizable elements:

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"}

The last recognizable element, the Golden Snitch (originally a live animal, called a Snidget), was originally part of a different sport of the same period:

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"}

The book goes on to describe how the two sports came together:

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"}

Although the sport would continue to be refined over the centuries (and a full recounting of its history is far too long for this format), this is the earliest mention of it known in-universe.