George Saunders has won the Man Booker Prize for his novel Lincoln In The Bardo.
The 58-year-old is the second American author to take home the coveted prize, worth £50,000.
The story focuses on the night former US President Abraham Lincoln buried his 11-year-old son Willie in a Washington cemetery.
Accepting his prize at the London ceremony on Tuesday, Saunders said: "In the US we're hearing a lot about the need to protect culture. Well this tonight is culture, it is international culture, it is compassionate culture, it is activist culture.
"It is a room full of believers in the word, in beauty and ambiguity and in trying to see the other person's point of view, even when that is hard."
This year's award was presented by the Duchess of Cornwall at the Guildhall in the City of London.