Booker Prize judges have rebelled against the rules and split the prestigious literary award between Margaret Atwood and Bernardine Evaristo.
Atwood has become the oldest Booker winner, at 79, and claimed her second win with The Testaments.
Evaristo has jointly triumphed following a shock decision to divide the £50,000 prize, despite rules forbidding this.
Final deliberations took five hours, with judges repeatedly told they were not allowed to split the prize, until they decided to make a "revolutionary gesture".
READ MORE: Photographer Shawna Law on Edinburgh's hidden gems
Those tasked with naming the winner "staged a sit-in", according to organisers, until their decision was accepted.
The two winners were announced at the Guildhall in London, where chairman of the jury and Hay Festival founder Peter Florence described the logic behind the literary revolt.
He said: "The more we talked about them, the more we treasured them and wanted them both as winners.
"Laws are invaluable. Rules are adapted to the circumstance.
"The only result that we were happy with was to award the prize this year to both.
"There are things they shared. They are both fully engaged novels. They address the world today."
READ MORE: Neil Forsyth on writing new BBC drama, Guilt
Mr Florence said the jury was unanimous in its decision to rebel, a decision Booker literary director Gaby Wood said she respected, despite an order from foundation chairwoman Helena Kennedy that the rules must be honoured.
She said: "It is always the jury's decision. I support the means by which the judges arrived at their decision.
"It wasn't a fighting gesture. It was a generous one.
"If someone makes a revolutionary gesture, you have to accept it. You don't have to say, 'I agree with it'."
Prolific Canadian author Atwood previously took home the prize in 2000 for her novel The Blind Assassin.
She has become the fourth person and the second woman to win the Booker twice, following Hilary Mantel, JM Coetzee and Peter Cary.
Mr Florence said of her work, which has been referenced by protest groups and follows on from The Handmaid's Tale, picking up the action 15 years later: "It's beautiful in its depth.
"Now it looks more politically urgent than ever. There is a need now to look at what complicity and what resilience and what resistance might look like."
British author Evaristo has been hailed for her polyvocal work Girl, Woman, Other, which explores the nature of modern British womanhood.
Mr Florence said the book provided a "wonderful spectrum of black British women today. This book is groundbreaking".
The Booker has been split twice before, between Nadine Gordimer and Stanley Middleton in 1974, and again between Michael Ondaatje and Barry Unsworth in 1992.
Rules were brought in following this to prevent future divisions of the prize.
Sir Salman Rushdie was shortlisted this year for his referential work Quichotte, along with Lucy Ellmann for Ducks, Newburyport, Chigozie Obioma for An Orchestra Of Minorities, and Elif Shafak for 10 Minutes 38 Seconds In This Strange World.
The jury was made up of Mr Florence, Liz Calder, novelist and film-maker Xiaolu Guo, writer and former barrister Afua Hirsch and composer Joanna MacGregor.
Why are you making commenting on The Herald only available to subscribers?
It should have been a safe space for informed debate, somewhere for readers to discuss issues around the biggest stories of the day, but all too often the below the line comments on most websites have become bogged down by off-topic discussions and abuse.
heraldscotland.com is tackling this problem by allowing only subscribers to comment.
We are doing this to improve the experience for our loyal readers and we believe it will reduce the ability of trolls and troublemakers, who occasionally find their way onto our site, to abuse our journalists and readers. We also hope it will help the comments section fulfil its promise as a part of Scotland's conversation with itself.
We are lucky at The Herald. We are read by an informed, educated readership who can add their knowledge and insights to our stories.
That is invaluable.
We are making the subscriber-only change to support our valued readers, who tell us they don't want the site cluttered up with irrelevant comments, untruths and abuse.
In the past, the journalist’s job was to collect and distribute information to the audience. Technology means that readers can shape a discussion. We look forward to hearing from you on heraldscotland.com
Comments & Moderation
Readers’ comments: You are personally liable for the content of any comments you upload to this website, so please act responsibly. We do not pre-moderate or monitor readers’ comments appearing on our websites, but we do post-moderate in response to complaints we receive or otherwise when a potential problem comes to our attention. You can make a complaint by using the ‘report this post’ link . We may then apply our discretion under the user terms to amend or delete comments.
Post moderation is undertaken full-time 9am-6pm on weekdays, and on a part-time basis outwith those hours.
Read the rules here