Writing on the book’s website, the author described the response as “one of the most meaningful experiences” of her writing career.
The 55-year-old expressed her gratitude to those who bought the book, thereby raising money for her charitable trust, Volant, which supports projects that alleviate social deprivation, particularly helping women, children and young people who are at risk.
The Ickabog was published in instalments online, before its official publication in November 2020. It was Rowling’s first children’s book since Harry Potter And The Deathly Hallows in 2007.
Rowling said writing the fairytale, about a mythical land called Cornucopia ruled by a monarch called King Fred, had reminded her of her love for children’s writing.
The bestselling author wrote in a post titled “A big thank you from JK Rowling”: “When I decided to put out chapters of The Ickabog for free during last year’s first coronavirus lockdown, the response was phenomenal and reminded me just how much I love writing for children.
“From reader engagement to the avalanche of the children’s pictures submitted to the illustration competition, sharing The Ickabog was a wonderful experience during a very dark time.
“I had no idea what to expect in terms of sales of the book, because so many people had already read the story for free.
“I certainly hoped we’d be able to shift a few copies, because all my royalties would be donated to my charitable trust, Volant, which would then distribute them to charities supporting groups particularly hard-hit by the pandemic, but, in truth, sales figures were the last thing on my mind.
“The Ickabog had been such a special project, I considered that it had done its job even if the printed book didn’t sell very well.
She added: “I was already happy that I’d brought The Ickabog down from the attic, but your extraordinary generosity has made this one of the most meaningful experiences of my writing career.”