The bestselling author recently published an new piece of writing revealing the backstory behind one of Hogwarts' most fascinating characters - the cruel Dolores Umbridge. The 5000-word essay was shared on Pottermore on Halloween this year.

This marks a nostalgic return to the magical world, after the success of Rowling's subsequent books - The Casual Vacancy and the Cormoran Strike crime series, written as Robert Galbraith. The Casual Vacancy has been adapted for the BBC to be shown over the Christmas period, but Harry Potter fans will be far more excited about new content.

JK Rowling once remarked that she had reams of Harry Potter backstory around the events of the novel and film series still in her head that could be written down. She said to fans when the series ended that "no story lives unless someone wants to listen. The stories we love best do live in us forever. So whether you come back by page or by the big screen, Hogwarts will always be there to welcome you home."

Words: Victoria Gray, Images: Rex Features

JK Rowling gives Harry Potter fans a Christmas treat with new writing released each day in the run up to Christmas