A US icon with a troubled past died in California on Sunday, aged 47, far more famous than he ever set out to be.

Rodney King, whose police brutality case in 1991 led to deadly riots in Los Angeles, was found dead by his girlfriend in the swimming pool of their home in Rialto, just outside Los Angeles.

Randy DeAnda of the Rialto Police Department said there were no immediate signs of foul play and the case is being investigated as a drowning.

1991 beating on tape

Rodney King rose to international attention when he was dragged from his truck in March 1991 after a lengthy car chase and beaten by LA police just over 20 years ago.

At the time King failed to stop because he'd been drinking and worried a DUI conviction would complicate the terms of the parole he was on from a previous jail sentence.

The beating was filmed by a bystander with a video - which was rare twenty years ago - long before the days of the ubiquitous cell phone camera.

"I'm just so glad that there was a video camera out there, and video cameras are everywhere now, you know? And it was hard for me to beat that case with the video camera. But I'm really glad that they're out there now, you know, and I'm glad that they started putting them on some patrol cars and stuff," King said of his beating caught on tape.

LA riots

A year after the beating, when the cops involved were acquitted by a jury, Los Angeles erupted in flames.

The rioting was some of the worst seen on US soil ... and it all played out live on TV.

More than 50 people died, over 2,000 were injured.

Upwards of 7,000 fires were set.

Damages to homes and businesses ran into a billion dollars.

Rodney King blurted out a memorable phrase at the time that will probably become his epitaph.

"Can we all get along ?"

Sad life

In the years since his beating, the subsequent trial and riots, Rodney King lived a sad but quiet life, contributing to books, newspaper articles and TV shows.

He even tried his hand at boxing.

But he never fully got over the 1991 beating, nor did he properly come to terms with his status as a symbol of racial intolerance in the nation.

In the weeks before his death he appeared on TV to mark the twentieth anniversary of his beating, published his memoirs and most recently commented on the Florida killing of an unarmed black teenager Travyon Martin.

But it's that horrific beating and King's simple words that followed it, that will be his lasting legacy - "People, I just want to say, can we all get along, can we all get along?"