A play which was first performed at Theatre 503 in Battersea after being rejected all over America has won a Laurence Olivier Award.

Katori Hall, the black female creator of The Mountaintop, made theatre history as the first non-white playwright to win an Olivier in the best play category.

The play, an imagined account of Martin Luther-King’s last evening before being shot, was staged in the 65-seat theatre last summer.

Paul Robinson, artistic director at Theatre 503, said: “It is a joy and it truly feels a little bit David and Goliath. We really weren't expecting to win.

“It was lovely to be on the list and equally lovely to sit down to dinner and feel a part of things but our eyes were certainly downward cast and buried in the table cloth when the nominees were read out.

“For a small theatre like ours it is transformational. It helps to put fringe theatre, as a channel to mainstream theatre, on the map and into people’s minds.”

Ms Hall, 28, from Memphis, Tennessee, brought her play to London after struggling to find a theatre willing to stage it in the US.

It received critical acclaim and sold out at Theatre 503, later moving to Trafalgar Studios in the West End.

Directed by James Dacre and starring David Harewood and Lorraine Burroughs, it revolves around a conversation between Luther-King and a motel cleaner.

The events take place after his famous “mountaintop” speech, the day before his assassination in 1968.

Harewood was nominated for best actor in the Evening Standard Awards and Burroughs for best actress in the Oliviers.

Critics said the play evoked the ordinary side of the man whose character had been distorted by legend.

Mr Robinson added: “What Katori wrote was this incredibly feisty woman who had her own opinions, who called him to account on things, who disagreed with him and who flirted with him.

“She did all these unexpected things with him which made for a much more dynamic and dramatic story.”