Bo Diddley, who died yesterday at 79, was a swaggering blues belter whose crackly feedback guitar riffs and infectious rhythms helped give birth to rock ‘n’ roll.

With homemade square guitars, replete with dials for electronic distortion boxes of his own devising, Diddley produced an unmistakable rock sound for such songs as “I’m a Man,” “Who Do You Love?,” and “You Can’t Judge a Book by Its Cover.” He rose from poverty in Chicago to become a seminal part of rock history, but he somehow missed out on superstardom of his own. Instead, he toured for decades and was periodically rediscovered, his material re-mined for hits by others. But having sold off his copyrights during tight years, he made little money, despite lending his name to the most famous beat in rock music.

The Bo Diddley beat is exemplified in the old show-business phrase “shave and a haircut, two bits.” Long a part of African-American music, it was also known as “hambone” because it could be slapped out on the thighs (hams). Bo Diddley knew it from church, where he played violin, drums, and even trombone. He left home while still a teenager because he also liked to play what his family called “devil’s music.”

A journeyman on the black-friendly Chitlin’ Circuit, Bo Diddley tasted real success in 1955, when he signed with Checker Records, a subsidiary of Chess Records in Chicago. He scored hits with “Bo Diddley” and “I’m a Man” — the latter a song lewd enough to make his condemnations of rap seem more than a little strained. Alan Fried, the New York disc jockey who coined the term “rock ‘n’ roll,” picked up both songs. Later that year, Diddley appeared on the Ed Sullivan Show and switched up on the host by playing his own “Bo Diddley” instead of the agreed-on “Sixteen Tons.” Sullivan was furious, and Diddley didn’t perform on television again for years.

Others found the new beat infectious. Buddy Holly lifted it for “Not Fade Away.” Later, the Rolling Stones, the Yardbirds, the Clash, and a host of others did the same. (Diddley would repeatedly decry the fact that under American copyright law, only songs and not beats or arrangements could be protected.)

When John Lennon was asked at the Beatles’ first New York news conference in 1964 what he was looking forward to seeing in America, he replied, “Bo Diddley.” Left behind was the performer himself.

“I opened the door for a lot of people, and they just ran through and left me holding the knob,” he told the New York Times in 2003.

Diddley was born Otha Ellas Bates onDecember 30, 1928, on a farm in McComb, Miss.. He never knew his father. He was raised by his mother’s cousin, Gussie McDaniel, who took him to Chicago in the mid-1930s. He became Ellas McDaniel, but early on he was called Bo Diddley. He gave at least a half-dozen explanations for the moniker, including that he took it as a ring name when he boxed semiprofessionally. Others attributed it to the diddley bow, a one-string blues instrument akin to the washtub bass he fiddled in early bands.

He took violin lessons at Ebenezer Baptist Church, but over time, and much to his family’s displeasure, became more interested in the blues guitar of John Lee Hooker. He started by playing in a washboard group on street corners, then graduated to Chicago’s lively blues club scene. In 1955, the Chicago Defender wrote that he was the equal of Bert Williams and Bill “Bojangles” Robinson. “From the time he hits the stage and strikes the first note his audiences go into a frenzy of hand clapping, outcries, chorus singing, and cheers,” the Defender wrote. “The whole house rocks with magic and girls have been known to faint from the excitement.” In his stubby boxer’s hands, the guitar somehow became a cross between an organ and the drums that he called “freight train style.” He added percussion from maracas, homemade from toilet tank floats. Nobody else sounded like Bo Diddley.

Flamboyant on stage, he dressed in black, affected big horn-rimmed glasses and a pompadour or Stetson. His act included his stepsister, the Duchess, on rhythm guitar, with sultry backup singers Cookie and Sleepy King. The way he moved his hindquarters, wrote the Washington Post in 1961, “makes Elvis Presley seem even a greater oaf.” But if stage audiences found him irresistible, chart success continued to elude him. Only one song, the proto-rap novelty tune “Say Man” (1959), ever cracked Billboard’s Top 20. He kept touring and cutting new records, typically featuring wild cover art depicting him in a Ben Hur outfit or as a gunslinger. Trying to catch a popular wave, he released “Surfin’ with Bo Diddley” in 1963. But nothing really caught on, and by the mid-1970s he was without a record contract and so neglected that Rolling Stone left him out of one of its histories of rock. At one point in the early 1970s, he moved to Los Lunas, N.M., and became a deputy sheriff.

Things picked up for him starting in 1979, when the Clash enlisted him as an opening act on an American tour. He began appearing at oldies shows in the 1980s, and he was an early entrant in the Rock and Roll Hall of Fame in 1987. A 1989 advertisement for Nike sneakers paired him with the athlete Bo Jackson.

Having left Los Angeles because of the earthquakes and New Mexico because of the snow, he settled at last on several-dozen acres near Gainesville, Fla. He recorded at his own studio and released albums on his own label, but sales were anemic.

In 2002, he said that he was recording a rap song about the coming war: “Saddam Hussein, pick up your phone, if you do we might leave you alone.”

Asked where the Bo Diddley beat came from, he told the author of “Bo Diddley: Living Legend,” George White: “I’d say it was mixed-up rhythm: blues and Latin American, and some hillbilly, a little spiritual, a little West Indian calypso. I like gumbo, you dig? Hot sauces, too. That’s where my music come from: all the mixture.”

He was married and divorced four times. Survivors include four children and at least 30 grandchildren and great-grandchildren.