David Oyelowo defends Selma role

David Oyelowo thinks it's better when he doesn't know too much about the character he's playing.

The British actor takes on a part of a lifetime, playing Martin Luther King Jr. in civil rights drama Selma.

It might seem strange for someone from the UK to portray the iconic American, but David reasons he's in good company.

"If Meryl Streep can play Margaret Thatcher, I can play Dr. King!" he exclaimed to Time Out London magazine.

"The truth is that this happens all the time. I was in The Last King of Scotland and Forest Whitaker was playing Idi Amin and could not be less Ugandan if he tried! Idris Elba played [Nelson] Mandela.

"I often think the less you know as an actor, the more fastidious you are about finding the person you're playing."

Selma has already been nominated for two Oscars - best motion picture and best achievement in music. David, 38, is pleased it's getting so much attention and stirring up a conversation about important issues.

"It's become more topical than we thought it would!" he smiled.

"But, look, you make films to engage society. Hopefully those films are thought-provoking and hopefully they hold a mirror up to you and your life. I am stimulated by these conversations because I think that just having the causes change."

The star added that he and director Ava DuVernay were keen to make something that wouldn't be dismissed as historical and fall into the category of "stuffy".