US-based Zambian writer Namwali Serpell has promised to share her winnings in the Caine Prize for African Writing with the runners up.
She received the £10,000 ($15,600) prize for her short story The Sack.
The judges described it as "innovative, stylistically stunning, haunting and enigmatic".
Ms Serpell was among five writers short-listed for the prize, regarded as Africa's leading literary award.
Two South Africans and two Nigerians were also shortlisted for the prize - Masande Ntshanga for Space, FT Kola for A Party for the Colonel, Elnathan John for Flying and Segun Afolabi for The Folded Leaf.
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Ms Serpell told BBC Newsday that the promise to share the winnings was "an act of mutiny".
"I wanted to change the structure of the prize.
"It is very awkward to be placed into this position of competition with other writers that you respect immensely and you feel yourself put into a sort of American idol or race-horse situation when actually, you all want to support each other."
The chair of judges, Zoe Wicomb, awarded the prize at a dinner held at the Bodleian Library at Oxford University in the UK.
The short story "yields fresh meaning with every reading," she said.
In The Sack, two men who live together their whole lives love one woman but don't know which one of them she loves.
"One of the men has a series of backwards moving dreams about his own death and he becomes very paranoid about the other man," Ms Serpell said.