Jennings -- one of the driving forces behind the so-called outlaw movement in country music three decades ago -- had been in poor health recently, and had undergone surgery in April and November 2001 in connection with treatment for peripheral vascular disease.
On Jan. 7, a spokeswoman for Jennings confirmed that his left foot was amputated in December after a diabetes-caused infection set in. Schatzi Hageman quoted Jennings as saying that he had been hobbling for more than two years, but was able to walk again with the use of a prosthetic.
Jennings said he expected to resume touring in a few months.
Known to his friends in the music business as "Waymore," Jennings recorded more than 73 albums -- including 13 consecutive multi-platinum, platinum and gold albums in the 1970s. In 1993, his "Greatest Hits" album went quadruple-platinum.
Jennings was a two-time Grammy Award winner and a member of the Country Music Hall of Fame.
Sam Lovullo, the creator of the long-running country music variety show "Hee Haw" and a member of the Country Music Hall of Fame nominating committee, said when Jennings first appeared on the show in 1969, he had everything going for him -- except for one obvious drawback.
"There was magic in his voice, it was a driving style, kind of like Johnny Cash," Lovullo told United Press International. "I hate to say this but if he had not been caught up in the drug scene at a young age, he would have been as big as Garth Brooks."
Jennings made no secret of his drug abuse, which he said ended when he began his relationship with his wife, singer Jessi Colter.
His greatest hits included "Are You Sure Hank Done It That Way," "Luckenbach, Texas," "Mammas Don't Let Your Babies Grow Up To Be Cowboys," "I've Always Been Crazy," "Just To Satisfy You," "Amanda," "Lucille," and "The Wurlitzer Prize."
Jennings became a country music superstar but his popularity crossed barriers into the pop and rock music genre.
Born in Littlefield, Texas, on June 15, 1937, Jennings showed a keen interest in music as a child and learned to play guitar chords before his teens. He grew up listening to folk songs and the music of seminal artists like Jimmie Rodgers, and later, to Hank Williams, Ernest Tubb, Webb Pierce, B.B. King and Bobbie "Blue" Bland.
He formed his own band at age 12 and was a radio deejay at 14.
Jennings was invited to join Buddy Holly's band, playing electric bass, when Holly was on the road to stardom. If not for a twist of fate, Jennings would have been killed in the plane crash that killed Holly, Ritchie Valens and J.P. Richardson (The Big Bopper) on a flight from clear Lake, Iowa to Fargo, N.D. on Feb. 3, 1959.
In his 1996 memoir, "Waylon: An Autobiography," Jennings provided the most complete accounting of how he gave his seat on the plane to Holly and joined other members of the band on a bus following a concert that night.
He said he and Holly had engaged in a good natured argument about the seat, and he settled it by telling Holly to go ahead and take the seat, joking that he hoped "you all crash."
The tragedy was a difficult burden for Jennings to carry, but he returned to Lubbock, Texas, to continue a career as a disc jockey and part-time musician. His association with Holly and the singer's tragic death helped to boost Jennings' career.
"Mainly what I learned from Buddy," said Jennings, "was an attitude. He loved music, and he taught me that it shouldn't have any barriers to it."
Jennings moved to Phoenix, Ariz., in the early 1960s and formed his own band, The Waylors.
Always noted for having a keen ear, he managed to combine elements of rock and country into a unique blend. Many musicians at the time ripped Jennings' style, but his growing popularity in the Phoenix area boosted the entertainer's career.
Bobby Bare, then a rising star with RCA, caught Jennings' act in a Phoenix nightclub and sent word to Chet Atkins, the label's chief executive in Nashville. Atkins signed Jennings to RCA, resulting in respectable showings for three new records, including "Anita You're Dreaming."
Jennings moved to Nashville in April 1966 and soon became roommates with Johnny Cash. The two stars developed a deep rapport.
Jennings appeared on the Grand Ole Opry, but his unique repertoire and personality did not endear him to the Nashville establishment. Even his dress irritated some executives, who expected rhinestone suits -- not the jeans and sports shirts he wore.
Jennings got back at them in his record, "Nashville Bum."
He recorded a number of hits in the mid and late '60s and won a Grammy in 1969 for "MacArthur Park," which he performed with the Kimberleys. Other hits at the time were "Mental Revenge," "Green River," "Walk On Out of My Mind," "Only Daddy That'll Walk the Line" and "I Got You."
Jennings was still looking for his first No. 1 hit in 1975 when his wife, Jessi Colter, scored her first No. 1. As he began to work with such writers as Kris Kristofferson, Mickey Newbury and Billy Joe Shaver, Jennings found the sound that would make him a top-line star in Nashville -- whether Nashville liked it or not.
He turned out "The Taker, "Cedartown, Georgia" and "Good Hearted Woman." He and Willie Nelson had a hit with "Ladies Love Outlaws," helping to propel Nelson's music career to new heights at around the same time.
Jennings, Nelson and Coulter released "Wanted! The Outlaws" with Tompall Glaser in 1976. The album -- a compilation of 11 previously released songs by the four -- was a giant hit, remaining on the country charts for years, and reaching the Top 10 on pop charts. His widening popularity eventually landed him a spot on the Lollapalooza music festival tour.
In the 1980s, he recorded and toured with Cash, Nelson and Kris Kristofferson as The Highwaymen.
He also had a voiceover role -- as a narrator called The Balladeer -- on the TV show, "The Dukes of Hazard" (1979-95). His theme for the show, "Good Old Boys," was also a chart hit.
Jennings and Colter collaborated in April 2000 on an album of children's music, "Around the World Sing-Along."