Peter Frampton Performs During Frampton"s Guitar Circus At Route 66 Casino's Legends Theater
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Legendary blues guitarist B.B. King has died at the age of 89.

His lawyer told the Associated Press that King died peacefully in his sleep at his Las Vegas home on Thursday night.

King, who was diagnosed with type 2 diabetes more than 20 years ago, was a famously relentless live performer well into his eighties. But his health has deteriorated in recent years: He was hospitalized twice in April, both times for dehydration, and he canceled a string of tour dates in the fall of 2014, following an erratic performance that April.

On May 1 he announced that he had entered hospice care at his Las Vegas home.

Born Riley B. King, his career began in earnest more than 65 years ago, following a 1948 breakout performance on Sonny Boy Williamson's Memphis radio show. In 1956, he performed 342 times with his band. His alliterative radio name, "Beale Street Blues Boy," shortened with time.

In 1965 he released Live at the Regal, named one of the 150 greatest albums of all time by Rolling Stone—a landmark work not just for its performer but for the genre as a whole.

"When he stepped onstage at the storied Regal Theater on Chicago's Southside in November 1964, B.B. King had 30 R&B hits but had barely creased the pop charts. Recorded that night, King's first live album would become an entry point for many white listeners, and blues aficionados still speak of it with awe," the magazine wrote in later crowning that album the No. 5 best live album of all time.

"The Thrill is Gone," his highest-charting hit, followed in 1969; and in 1979 he became the first R&B performer to tour the Soviet Union, two years after receiving an honorary doctorate from Yale University and just five years before being inducted into the Blues Foundation Hall of Fame.

By 1985, he had recorded 30 studio albums; and by 1987 he received a Grammy Lifetime Achievement Award – a full 21 years before his final album, 2008's One Kind Favor. In 2010 President George W. Bush awarded him the Presidential Medal of Freedom, the nation's highest civilian honor.

"A lot of times from the beginning, I was kind of worried about it, but we had to hitchhike from place to place to try to get a job. But you, ladies and gentlemen, have made it worth every moment that I said I’d make 38 years and I thank you very much," King said when he was inducted into the Rock and Roll Hall of Fame in 1987.

All along King played with "Lucille," the name he gave to the string of guitars that accompanied him onstage. But not to be cute, Time music critic Josh Tyrangiel once wrote, honoring him as one of music's greatest electric guitarists: "With King's emphasis on vibrato, she sounds like a real woman singing the blues."

In 2005, King's home state declared Feb. 15 "B.B. King Day," and he wept at the news, the first time he said he'd cried since the death of friend Ray Charles.

"That was tears of sorrow. Today, it was tears of joy."