Harry’s book is called Spare, a reference to the phrase "the heir and the spare”, and will be released globally on January 10.
On a promotional website for the new book, publisher Penguin Random House said Harry would support British charities with donations from the proceeds, including Sentebale and WellChild.
Buckingham Palace is still likely to be steeling itself for revelations that could be detrimental to the monarchy and the duke’s father Charles, now King and in the early stages of his reign.
The royal family could be faced with damaging newspaper headlines if Harry chooses to delve into the most controversial elements of royal life from recent decades.
A key part of the duke’s life is the break-up of his parent’s marriage and the death of his mother Diana in a Paris car crash in 1997.
Little is known about life behind palace walls for the duke and his older brother William during this difficult period, with Harry only saying years later how he tried to block out the pain of losing his mother.
The blurb on the website reads: “It was one of the most searing images of the 20th century: two young boys, two princes, walking behind their mother’s coffin as the world watched in sorrow – and horror. As Diana, Princess of Wales, was laid to rest, billions wondered what the princes must be thinking and feeling – and how their lives would play out from that point on.
“For Harry, this is that story at last.
“With its raw, unflinching honesty, Spare is a landmark publication full of insight, revelation, self-examination, and hard-won wisdom about the eternal power of love over grief.”
A description under the heading “about the author” reads: “Prince Harry, The Duke of Sussex, is a husband, father, humanitarian, military veteran, mental wellness advocate, and environmentalist. He resides in Santa Barbara, California, with his family and three dogs.”
Prince Harry book release date
Penguin Random House said the memoir will be available in English in the UK, Ireland, Australia, New Zealand, India, South Africa and Canada, while the book will also be published in translation in 15 additional languages, including Spanish, Italian, German and Chinese.
The book is available to pre-order on the official Spare site.