Which J.K. Rowling novel won the 1999 Whitbread Children's Book of the Year award?

J.K. Rowling’s Harry Potter and the Prisoner of Azkaban won the 1999 Whitbread Children’s Book of the Year award.

The novel was published in the United Kingdom on 8 July 1999 and is the third book in the original Harry Potter series. Its story introduces Sirius Black’s escape from the wizarding prison of Azkaban and expands the history of Harry’s parents and their friends.

The award was a notable achievement because the Whitbread prize was a major British literary award open to books beyond children’s fiction. Rowling’s win helped demonstrate that a popular fantasy series could also receive recognition from the wider literary world.

It is sometimes confused with the Nestlé Smarties Book Prize, which several Harry Potter novels also won. The Whitbread honor specifically refers to the 1999 children’s-book category.