Led Zeppelin was the definitive heavy metal band. It wasn't just their crushingly loud interpretation of the blues -- it was how they incorporated mythology, mysticism, and a variety of other genres (most notably world music and British folk) -- into their sound. Led Zeppelin had mystique. They rarely gave interviews, since the music press detested the band. Consequently, the only connection the audience had with the band was through the records and the concerts. More than any other band, Led Zeppelin established the concept of album-oriented rock, refusing to release popular songs from their albums as singles. In doing so, they established the dominant format for heavy metal, as well as the genre's actual sound.

Led Zeppelin formed out of the ashes of the Yardbirds. Jimmy Page had joined the band in its final days, playing a pivotal role on their final album, 1967's Little Games, which also featured string arrangements from John Paul Jones. During 1967, the Yardbirds were fairly inactive. While the Yardbirds decided their future, Page returned to session work in 1967. In the spring of 1968, he played on Jones' arrangement of Donovan's "Hurdy Gurdy Man." During the sessions, Jones requested to be part of any future project Page would develop. Page would have to assemble a band sooner than he had planned. In the summer of 1968, the Yardbirds' Keith Relf and James McCarty left the band, leaving Page and bassist Chris Dreja with the rights to the name, as well as the obligation of fulfilling an upcoming fall tour. Page set out to find a replacement vocalist and drummer. Initially, he wanted to enlist singer Terry Reid and Procol Harum's drummer B.J. Wilson, but neither musician was able to join the group. Reid suggested that Page contact Robert Plant, who was singing with a band called Hobbstweedle.

After hearing him sing, Page asked Plant to join the band in August of 1968, the same month Chris Dreja dropped out of the new project. Following Dreja's departure, John Paul Jones joined the group as its bassist. Plant recommended that Page hire John Bonham, the drummer for Plant's old band, the Band of Joy. Bonham had to be persuaded to join the group, as he was being courted by other artists who offered the drummer considerably more money. By September, Bonham agreed to join the band. Performing under the name the New Yardbirds, the band fulfilled the Yardbirds' previously booked engagements in late September 1968. The following month, they recorded their debut album in just under 30 hours. Also in October, the group switched its name to Led Zeppelin. The band secured a contract with Atlantic Records in the United States before the end of the year. Early in 1969, Led Zeppelin set out on their first American tour, which helped set the stage for the January release of their eponymous debut album. Two months after its release, Led Zeppelin had climbed into the U.S. Top Ten. Throughout 1969, the band toured relentlessly, playing dates in America and England. While they were on the road, they recorded their second album, Led Zeppelin II, which was released in October of 1969. Like its predecessor, Led Zeppelin II was an immediate hit, topping the American charts two months after its release and spending seven weeks at number one. The album helped establish Led Zeppelin as an international concert attraction, and for the next year, the group continued to tour relentlessly. Led Zeppelin's sound began to deepen with Led Zeppelin III. Released in October of 1970, the album featured an overt British folk influence. The group's infatuation with folk and mythology would reach a fruition on the group's untitled fourth album, which was released in November of 1971. Led Zeppelin IV was the band's most musically diverse effort to date, featuring everything from the crunching rock of "Black Dog" to the folk of "The Battle of Evermore," as well as "Stairway to Heaven," which found the bridge between the two genres. "Stairway to Heaven" was an immediate radio hit, eventually becoming the most played song in the history of album-oriented radio; the song was never released as a single. Despite the fact that the album never reached number one in America, Led Zeppelin IV was their biggest album ever, selling well over 16 million copies over the next two and a half decades.