Margaret Atwood and Bernardine Evaristo jointly won the 2019 Booker Prize on Monday after judges "flout" the rules by declaring a tie.
British Indian novelist Salman Rushdie's tragicomic 'Quichotte' was among the six books shortlisted for the prize.
The Booker rules say the prize must not be divided, but the judges insisted they "couldn't separate" Atwood's 'The Testament' and 'Girl, Woman, Other' by Evaristo, who is the first black woman to win the prestigious award since its creation in 1969.
The rules were changed after the last tie in 1992, and organisers told this year's judges that they were not allowed to pick two winners.
But after five hours of deliberations, Peter Florence, the chair of the five-member judging panel, said: "It was our decision to flout the rules."
Atwood joked to her co-winner: "I would have thought I would have been too elderly, and I kind of don't need the attention, so I'm very glad that you're getting some."
Evaristo said, "We black British women know that if we don't write ourselves into literature no one else will."
On Rushdie's 'Quichotte' the judging panel commented, "A picaresque tour-de-force of contemporary America, with all its alarms and craziness. Rushdie conjures a celebration of storytelling and language that will delight lovers of Cervantes, lovers of daytime television and lovers of life."
Florence, founder and director of the Hay Festival and Chair of the Booker Prize judging panel this year, said: The common thread is our admiration for the extraordinary ambition of each of these books."
"Anyone who reads all six of these books would be enriched and delighted, would be awe-struck by the power of story, and encouraged by what literature can do to set our imaginations free."