Many of King's blues contemporaries, such as Lightnin' Hopkins, John Lee Hooker and Muddy Waters, consciously played to their rural roots, but King's style drew on gospel music and big-band jazz. As a consequence, he found a much wider audience.
King grew up in the Jim Crow South and lived to see the blues evolve into a musical hybrid. Performers, both black and white, embraced his style as the distinctions between blues, rock and soul gradually blurred.
His career reflected an intense drive for self-improvement. King conquered a childhood stammer to become a radio performer in the late 1940s. After learning music by ear, he studied music theory from books between engagements. While averaging more than 300 shows a year, he still found time to study for his pilot's licence.
He also struggled to earn respect for himself and for the blues, a genre that many African Americans deemed passe by the 1960s. At the Royal Theatre in Baltimore, he said black teenagers once booed him after loudly applauding acts such as the Drifters and Sam Cooke.
"My only ambition is to be one of the great blues singers and be recognised," King told music journalist Michael Lydon in 1974. "If Frank Sinatra can be tops in his field, Nat Cole in his, Bach and Beethoven and those guys in theirs, why can't I be great and known for it in the blues?"
His touring career began in the 1950s with one-nighters on the "chitlin' circuit" - taverns and small theatres that catered to predominantly black audiences. King was a steady seller on the R&B charts with such hits as Woke Up This Morning (1953), Every Day I Have the Blues (1955), Please Accept My Love (1958), Sweet Sixteen (1960) and Rock Me Baby (1964).
In the late 1960s, an aggressive new manager, Sid Seidenberg, pushed King into an entirely different set of venues just as blues-rock musicians such as Clapton and Paul Butterfield were fostering an awareness of blues among white listeners.
Seidenberg booked the bluesman into the Fillmore West in San Francisco - his first engagement in front of a counterculture and rock audience - and Caesars Palace in Las Vegas, a venue more associated with pop stars such as Frank Sinatra and Dean Martin. The manager also lined up TV appearances on The Ed Sullivan Show and The Tonight Show.
At 45, after two decades of hits on the R&B charts and nonstop touring, King broke through on the pop charts in 1970 with The Thrill Is Gone.
The song had already been an R&B hit in 1951 for blues singer Roy Hawkins. King's update set the doleful lyrics against an up-tempo, danceable rhythm pushed along by bassist Jerry Jemmott.
With a contemporary beat and the addition of orchestral strings, the record marked a slight change in direction for King and brought him wide commercial success.
The record won two Grammys, first in 1970 then nearly two decades later in 1998, when it was named a Hall of Fame recording. In total, King received 15 Grammy awards and, in 1988, was given a lifetime achievement Grammy. In 1991, he was awarded the National Medal of Arts and four years later the Kennedy Centre Honours.
In 2006, President George W. Bush bestowed on King the Presidential Medal of Freedom, the nation's highest civilian award.
Although he was not a dancer or physical entertainer like James Brown or Jackie Wilson, King developed a strong rapport with audiences by conversing with them. His stories were wry, but almost sermonic in style, and often told from the viewpoints of both sexes.
"Ladies, if you've got a man, husband, whatever you wanna call him," he said on a concert recording, "and he don't do exactly like you think he should, don't cut him because you can't raise him over again.
"And fellas, I want say to you, if you got a wife, a woman or whatever you wanna call her, and she don't do like you think she should, don't go upside her head. That don't do but one thing. That make her a little smarter - she won't let you catch her the next time."
Riley B. King was born on September 16, 1925 on a plantation near Itta Bena, Mississippi, to a sharecropping family. He said he never knew what his middle initial stood for; his stage name, BB, was short for Blues Boy, from his early radio billing as the Beale St Blues Boy.
King's parents split up when he was 4, and his mother died when he was 9. King ran away from his father's home and settled in Indianola, Mississippi, supporting himself by picking cotton. He discovered blues through 78rpm records by singers Lonnie Johnson and Blind Lemon Jefferson.
A minister taught him the rudiments of the guitar and, at 18, King joined a local gospel quartet. He later busked on Beale St in Memphis with a cousin, Delta blues guitarist Bukka White.
King bought an electric guitar after seeing a performance by bluesman T-Bone Walker. He cajoled his way on to a live radio broadcast in Clarksdale, Mississippi, hosted by singer and harmonica player Rice Miller, better known as Sonny Boy Williamson.
Williamson allowed King to perform on air and asked listeners to call the station if they liked his music. Unbeknown to King, Williamson had booked himself two jobs at local juke joints, one paying US$12 ($16) and the other US$100, on the same night. Williamson called the lower-paying venue to cancel and instead offered up the services of King, the "new sensation" who was "burning up the phone lines".
"He said, 'I'm going to send him down in my place'," King once recalled. "He told me, 'You better play good, boy, because if you don't, you'll have to answer to me' ... I liked it very much, because it was my job to entertain the ladies while the fellers went in the back and played cards."
It was in this period that he took to calling his many guitars Lucille.
"Lucille got her name in a nothing town by the name of Twist, Arkansas," he told music writer Lydon. "We were playing some club, and some guys were fightin' and they knocked over a kerosene barrel and burned the place down.
"I almost got killed going back in to save my guitar, and when I found out the fight was over a gal named Lucille, I named my guitar that to tell me to keep her close and treat her right."
King first recorded in 1949 - as a singer, not a guitarist - and was later brought to Modern Records, a Los Angeles record label, by its Memphis-based talent scout, Ike Turner. Turner recorded King's first hit in 1951 with Three O'Clock Blues, in the back room of the Memphis YMCA.
By 1955, King was touring nationally with his own 10-piece band - an impeccably attired unit with a large horn section. Although his records were on the R&B charts, King grew frustrated with the label owners' cavalier approach to publishing and their practice of relegating his albums to the 98c budget bins.
In 1963, King contracted with the larger ABC Records and, two years later, released BB King Live at the Regal. The album, one of Rolling Stone magazine's "top 500 greatest albums of all time", captured his live act before a predominantly black audience on Chicago's South Side.
Critics cited the way the singer and the audience "had church" - the audience screaming and talking back in response to his songs.
In 1988, King sang with U2 on When Love Comes to Town from the band's album Rattle and Hum. The song's video introduced him to a younger generation of fans.
Its success also generated King's duets with rock, pop and hip-hop performers on albums such as Deuces Wild (1997). Among his most popular collaborations was a recording with Clapton, Riding With the King (2000).
King struggled with a weight problem and was diagnosed with type 2 diabetes in the 1980s. In later years, his condition forced him to perform in a chair.
In recent decades, King became a multimillionaire from his many TV commercials for Wendy's, Burger King, Texaco and other companies.
In the 1990s, he opened an eponymous nightclub on Memphis' redeveloped Beale St, later adding clubs in New York, Nashville and Orlando. In 2006, the BB King Museum and Delta Interpretive Centre in Indianola opened with exhibits that set his life in the context of world events.
His marriages to Martha Denton and Sue Hall both ended in divorce. In Blues All Around Me, King said that he had 15 children from his various relationships.
King felt compelled to continue touring, almost as if the hard road that led to the top could never end. "If I don't keep doing it, keep going, they'll forget me," he told the New York Times in 2003.
He often reminded people of those hard times - and the hard road - when he told the story of the 1949 fire in which he nearly lost his guitar.
"I usually say you can get another guitar, but not another BB King."
BB King
Born: September 16, 1925 on a cotton plantation near the town of Itta Bena in Mississippi.
Died: Yesterday aged 89 at his home in Las Vegas.
Real name: Riley B. King. He said he never knew what his middle initial stood for and that BB stood for Blues Boy, from his early radio billing as the Beale St Blues Boy. Also earned the nickname the King of the Blues.
- Washington Post
