Harry Potter author J.K. Rowling has revealed that she conceived of one of the major characters, Hogwarts school headmaster Albus Dumbledore, as gay.

She drew a round of applause from a packed house in New York's Carnegie Hall on Friday after making the revelation in response to an audience question.

J.K. Rowling, shown in July, told a New York audience she has always regarded her books as a 'prolonged argument for tolerance.'
(Ian West/Associated Press)

Rowling, appearing in New York as part of a North American book tour, was asked if Dumbledore ever found "true love."

"I always thought Dumbledore is gay," she said and explained that the character had fallen in love as a young man with Gellert Grindelwald, who later became a rival.

Dumbledore was "terribly let down" when Grindelwald turned out to be more interested in the dark arts than good, and the love turned into a "great tragedy," as he must destroy Grindelwald in battle, Rowling said.

"Falling in love can blind us to an extent," she said.

The audience gasped in response to the explanation, then applauded.

"I would have told you earlier if I knew it would make you so happy," she said.

Rowling said she had already revealed Dumbledore's sexuality to David Yates, director of Harry Potter and the Half-Blood Prince, after seeing a scene in the script in which Dumbledore reminisces about an attraction to a young woman.

She said she crossed it out and wrote "Dumbledore is gay" over that section of the script.

The film version of Harry Potter and the Half-Blood Prince, the sixth book in the series, is due for release late next year.

Rowling is giving readings from the final book, Harry Potter and the Deathly Hallows, in a tour that will bring her to Toronto next week for an appearance at the International Festival of Authors.

Rowling added that she always regarded her novels as a "prolonged argument for tolerance."

Harry Potter fans have long speculated over Dumbledore's sexuality, in part because of his mysterious past and lack of ties with female characters.

Websites devoted to the books about the boy wizard are now buzzing with the news, with mixed reaction from fans.

Some fans welcomed the news about Dumbledore, saying it adds a new dimension to the story, but others said it was unnecessary for Rowling to make the revelation.