King became known around the world after he and some friends were stopped by Los Angeles police on March 3, 1991, after a high-speed chase. King was beaten by baton-wielding officers while a bystander videotaped them. The video prompted a national debate on police brutality and race relations.
When the officers were cleared of brutality charges a year later, riots broke out in Los Angeles, resulting in 53 deaths and an estimated $1 billion in damage. During the riots, King made a famous televised appeal for calm, saying: "Can we all get along?"
Two of the officers were later convicted on federal charges of violating King's civil rights and were sentenced to prison. A jury ordered the city of Los Angeles to pay King, who was unemployed at the time of the beating, $3.8 million in damages.
Activist Reverend Al Sharpton called King a powerful civil rights symbol who "made America focus on the presence of profiling and police misconduct."
"Through all that he had gone through, with his beating and his personal demons, he was never one to not call for reconciliation and for people to overcome and forgive," Sharpton said in a statement.
King had a history of substance abuse and previously appeared on the U.S. cable TV program "Celebrity Rehab."
This year, two decades after the riots, King wrote a book entitled "The Riot Within: My Journey from Rebellion to Redemption." In a statement, Los Angeles Police Chief Charlie Beck said King had earned "a unique spot in both the history of Los Angeles and the LAPD."
Beck said King's legacy "should not be the struggles and troubles of his personal life, but the immensely positive change his existence wrought on this city and its police department."
King, who has three children, was engaged to marry Cynthia Kelley, a juror in the civil suit he brought against the city of Los Angeles, according to the biography that accompanied his book.
The Los Angeles Times published a quote that King gave the newspaper this year: "I would change a few things, but not that much. Yes, I would go through that night, yes I would. I said once that I wouldn't, but that's not true. It changed things. It made the world a better place."