For 17 years, Harry Potter wasn’t just a figment of author J.K. Rowling’s imagination, and Hogwarts wasn’t merely a fictional boarding school where children learned wizardry and magic. Rowling gave life to Harry, and, she says in an exclusive interview with TODAY, vice versa.

The world’s first billionaire author told TODAY co-host Meredith Vieira that it feels “incredible” to finally have ended the saga that will forever define a generation of readers of all ages.

“It feels great, to be honest with you. It’s a really nice place to be,” said Rowling.

But it took Rowling some time to get there. When she actually finished writing, months before last Saturday’s release of “Harry Potter and the Deathly Hallows,” Rowling said she was difficult to be around.

“I felt devastated,” she said, explaining she was just drained emotionally after having completed the seventh and final book in the series.

Inspiring story
Rowling was a young, divorced, single mother on public assistance when she began writing the Harry Potter saga in a café.

The first printing of the first book was only 50,000 copies, and she had no assurance that the book would sell and that the seven-part story she had already plotted out would ever be published in its entirety.

The book caught on rather well, the series selling hundreds of millions of copies in scores of languages, inspiring a series of movies that have brought the rich and complex world she created to life.

The fantasy world she envisioned and captured on paper has made Rowling a real-life billionaire.

Today, she owns two homes in Scotland and one in London and is married to Neil Michael Murray. She has two children with Murray, David Gordon Rowling Murray and MacKenzie Jean Rowling Murray, and a daughter from her first marriage, Jessica.

“When you started, you were not in the same place you are now by any means,” Vieira observed.

“No,” Rowling admitted. “And, in fact, when I started actually I was in a bad place. And then, you know, life has its ups and downs. So I mean, Harry’s been with me as a result. I think it was that feeling more than any other that I wouldn’t have that world to retreat into again that was painful.”

‘Cathartic moment’
Rowling, who will be 42 on July 31, has said elsewhere that she sobbed as she was writing the final chapters of “Deathly Hallows,” which sold 8.3 million copies in the United States on the day of its release.

“It was this amazing cathartic moment,” she told Vieira. “The end of 17 years of work. And that was just hard to deal with for about a week. And it’s very much tied into things I’ve done in my life for seven years that brought back a lot of memories of what had been going on in my life when I started writing.”

She knows what she has done. “I feel a big sense of achievement,” she told Vieira. “I mean, I am sad. But I’ve been sadder.”

For about a week after she finished the series, she admitted, “I was hard to live with.”

It’s not an uncommon emotion among writers. Truman Capote once observed that finishing a novel is like taking your firstborn son into the yard and shooting him. Rowling was not that dramatic, but her readers, who even now are picking up “Deathly Hallows” and cradling the book with tenderness, knowing there will not be another, can understand something of what she felt.

So what does an author do when the final book is done?

“I need to be off writing,” she told Vieira.

TODAY will air more of the exclusive interview with J.K. Rowling on Thursday and Friday. Portions are scheduled to air Sunday on “Dateline NBC.”

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