Early lyrics drew on the band's blues and folk roots, often mixing lyrical fragments from different songs. Many of the band's songs dealt with themes of romance, unrequited love and sexual conquest, which were Common in rock, pop and blues music. Some of their lyrics, especially those derived from the blues, have been interpreted as misogynistic. Particularly on Led Zeppelin III, they incorporated elements of mythology and mysticism into their music, which largely grew out of Plant's interest in legends and history. These elements were often taken to reflect Page's interest in the occult, which resulted in accusations that the recordings contained subliminal satanic messages, some of which were said to be contained in backmasking; these claims were generally dismissed by the band and music critics. Susan Fast argues that as Plant emerged as the band's main lyricist, the songs more obviously reflected his alignment with the West Coast counterculture of the 1960s. In the later part of the band's career Plant's lyrics became more autobiographical, and less optimistic, drawing on his own experiences and circumstances.

In 1966, London-based session Guitarist Jimmy Page joined the blues-influenced rock band the Yardbirds to replace Bassist Paul Samwell-Smith. Page soon switched from bass to lead guitar, creating a dual lead guitar line-up with Jeff Beck. Following Beck's departure in October 1966, the Yardbirds, tired from constant touring and recording, began to wind down. Page wanted to form a supergroup with him and Beck on guitars, and the Who's Keith Moon and John Entwistle on drums and bass, respectively. Vocalists Steve Winwood and Steve Marriott were also considered for the project. The group never formed, although Page, Beck, and Moon did record a song together in 1966, "Beck's Bolero", in a session that also included bassist-keyboardist John Paul Jones.

The band began their first tour of the UK on 4 October 1968, still billed as the New Yardbirds; they played their first show as Led Zeppelin at the University of Surrey in Battersea on 25 October. Tour manager Richard Cole, who would become a major figure in the touring life of the group, organised their first North American tour at the end of the year. Their debut album, Led Zeppelin, was released in the US during the tour on 12 January 1969, and peaked at number 10 on the Billboard chart; it was released in the UK, where it peaked at number 6, on 31 March. According to Steve Erlewine, the album's memorable guitar riffs, lumbering rhythms, psychedelic blues, groovy, bluesy shuffles and hints of English folk, made it "a significant turning point in the evolution of hard rock and heavy metal".

The band saw their albums as indivisible, complete listening experiences, disliking the re-editing of existing tracks for release as singles. Grant maintained an aggressive pro-album stance, particularly in the UK, where there were few radio and TV outlets for rock music. Without the band's consent, however, some songs were released as singles, particularly in the US. In 1969 an edited version of "Whole Lotta Love", a track from their second album, was released as a single in the US. It reached number four in the Billboard chart in January 1970, selling over one million copies and helping to cement the band's popularity. The group also increasingly shunned television appearances, citing their preference that their fans hear and see them in live concerts.

Led Zeppelin have influenced hard rock and heavy metal bands such as Deep Purple, Black Sabbath, Rush, Queen, Aerosmith, the Black Crowes, and Megadeth as well as progressive metal bands like Tool and Dream Theater. They influenced some early punk and post-punk bands, among them the Ramones, Joy Division and the Cult. They were also an important influence on the development of alternative rock, as bands adapted elements from the "Zeppelin sound" of the mid-1970s, including the Smashing Pumpkins, Nirvana, Pearl Jam, and Soundgarden. Bands and artists from diverse genres have acknowledged the influence of Led Zeppelin, such as Madonna, Shakira, Lady Gaga, Kesha, and Katie Melua.

Led Zeppelin released their fourth album on 8 November 1971. In response to the treatment they had received from critics, particularly after Led Zeppelin III, the band decided to release the fourth album with no title, though it is variously referred to as Led Zeppelin IV, Untitled, IV, or, due to the four symbols appearing on the record label, as Four Symbols, Zoso or Runes. In addition to lacking a title, the original cover featured no band name, as the group wished to be anonymous and to avoid easy pigeonholing by the press. With 37 million copies sold, Led Zeppelin IV is one of the best-selling albums in history, and its massive popularity cemented Led Zeppelin's status as superstars in the 1970s. By 2006, it had sold 23 million copies in the United States alone. The track "Stairway to Heaven", never released as a single, was the most requested and most played song on American rock radio in the 1970s. The group followed up the album's release with tours of the UK, Australasia, North America, Japan, and the UK again from late 1971 through early 1973.

Houses of the Holy topped charts worldwide, and the band's subsequent concert tour of North America in 1973 broke records for attendance, as they consistently filled large auditoriums and stadiums. At Tampa Stadium in Florida, they played to 56,800 fans, breaking the record set by the Beatles' 1965 Shea Stadium concert and grossing $309,000. Three sold-out shows at Madison Square Garden in New York City were filmed for a motion picture, but the theatrical release of this project (The Song Remains the Same) was delayed until 1976. Before the final night's performance, $180,000 of the band's money from gate receipts was stolen from a safe deposit box at the Drake Hotel.

In 1974, Led Zeppelin took a break from touring and launched their own record label, Swan Song, named after an unreleased song. The record label's logo, based on a drawing called Evening: Fall of Day (1869) by william Rimmer, features a picture of Apollo. The logo can be found on Led Zeppelin memorabilia, especially T-shirts. In addition to using Swan Song as a vehicle to promote their own albums, the band expanded the label's roster, signing artists such as Bad Company, the Pretty Things and Maggie Bell. The label was successful while Led Zeppelin existed, but folded less than three years after they disbanded.

Following their triumphant Earls Court appearances, Led Zeppelin took a holiday and planned an autumn tour in America, scheduled to open with two outdoor dates in San Francisco. In August 1975, however, Plant and his wife Maureen were involved in a serious car crash while on holiday in Rhodes, Greece. Plant suffered a broken ankle and Maureen was badly injured; a blood transfusion saved her life. Unable to tour, he headed to the Channel Island of Jersey to spend August and September recuperating, with Bonham and Page in tow. The band then reconvened in Malibu, California. During this forced hiatus much of the material for their next album, Presence, was written.

Because of Plant's injuries, Led Zeppelin did not tour in 1976. Instead, the band completed the concert film The Song Remains the Same and the accompanying Soundtrack album. The film premiered in New York City on 20 October 1976, but was given a lukewarm reception by critics and fans. The film was particularly unsuccessful in the UK, where, unwilling to tour since 1975 because of their tax exile status, Led Zeppelin faced an uphill battle to recapture the public's affection.

In 1977, Led Zeppelin embarked on another major concert tour of North America. The band set another attendance record, with an audience of 76,229 at their Silverdome concert on 30 April. It was, according to the Guinness Book of Records, the largest attendance to that date for a single act show. Although the tour was financially profitable, it was beset by off-stage problems. On 19 April, over 70 people were arrested as about 1,000 fans tried to gatecrash Cincinnati Riverfront Coliseum for two sold-out concerts, while others tried to gain entry by throwing rocks and bottles through glass doors. On 3 June, a concert at Tampa Stadium was cut short because of a severe thunderstorm, despite tickets indicating "Rain or Shine". A riot broke out, resulting in arrests and injuries.

In August 1979, after two warm-up shows in Copenhagen, Led Zeppelin headlined two concerts at the Knebworth Music Festival, playing to a crowd of approximately 104,000 on the first night. A brief, low-key European tour was undertaken in June and July 1980, featuring a stripped-down set without the usual lengthy jams and solos. On 27 June, at a show in Nuremberg, Germany, the concert came to an abrupt halt in the middle of the third song, when Bonham collapsed onstage and was rushed to hospital. Speculation in the press suggested that his collapse had been the result of excessive alcohol and drug use, but the band claimed that he had simply overeaten.

Led Zeppelin also made a significant cultural impact. Jim Miller, Editor of Rolling Stone Illustrated History of Rock & Roll, argues that "on one level, Led Zeppelin represents the final flowering of the sixties' psychedelic ethic, which casts rock as passive sensory involvement". Led Zeppelin have also been described as "the quintessential purveyors" of masculine and aggressive "cock rock", although this assertion has been challenged. The band's fashion-sense has been seminal; Simeon Lipman, head of pop culture at Christie's auction house, has commented that "Led Zeppelin have had a big influence on fashion because the whole aura surrounding them is so cool, and people want a piece of that". Led Zeppelin laid the foundation for the big hair of 1980s glam metal bands such as Mötley Crüe and Skid Row. Other Musicians have also adapted elements from Led Zeppelin's attitude to clothes, jewellery and hair, such as the hipster flares and tight band T-shirts of Kings of Leon, Shaggy hair, clingy T-shirts and bluesman hair of Jack White of the White Stripes, and Kasabian Guitarist Sergio Pizzorno's silk scarves, trilbies and side-laced tight jeans.

Following Zeppelin's dissolution, the first significant project for the members was the Honeydrippers, which Plant initially formed in 1981, and which released its only album in 1984. The group featured Page on lead guitar, along with studio Musicians and friends of the pair, including Jeff Beck, Paul Shaffer, and Nile Rodgers. Plant focused on a different direction from Zeppelin, playing standards and in a more R&B style, highlighted by a cover of "Sea of Love" that peaked at number three on the Billboard chart in early 1985.

On 13 July 1985, Page, Plant, and Jones reunited for the Live Aid concert at JFK Stadium, Philadelphia, playing a short set featuring drummers Tony Thompson and Phil Collins, and Bassist Paul Martinez. Collins had contributed to Plant's first two solo albums while Martinez was a member of Plant's solo band. The performance was marred by a lack of rehearsal with the two drummers, Page's struggles with an out-of-tune guitar, poorly functioning monitors, and Plant's hoarse voice. Page described the performance as "pretty shambolic", while Plant characterised it as an "atrocity".

Led Zeppelin have been credited with a major impact on the nature of the music Business, particularly in the development of album-orientated rock (AOR) and stadium rock. In 1988 John Kalodner, then-A&R executive of Geffen Records, remarked that "In my opinion, next to the Beatles they're the most influential band in history. They influence the way music is on records, AOR radio, concerts. They set the standards for the AOR-radio format with 'Stairway to Heaven,' having AOR hits without necessarily having Top 40 hits. They're the ones who did the first real big arena concert shows, consistently selling out and playing stadiums without support. People can do as well as them, but nobody surpasses them". Andrew Loog Oldham, the former Producer and manager of the Rolling Stones, commented on how Led Zeppelin had a major influence on the record Business, and the way rock concerts were managed and presented to huge audiences.

The first Led Zeppelin box set, featuring tracks remastered under Page's supervision, was released in 1990 and bolstered the band's reputation, leading to abortive discussions among members about a reunion. This set included four previously unreleased tracks, including a version of Robert Johnson's "Travelling Riverside Blues". The song peaked at number seven on the Billboard Album Rock Tracks chart. 1992 saw the release of the "Immigrant Song"/"Hey, Hey, What Can I Do" (the original B-side) as a CD single in the US. Led Zeppelin Boxed Set 2 was released in 1993; the two box sets together contained all known studio recordings, as well as some rare live tracks.

In 1994, Page and Plant reunited for a 90-minute "UnLedded" MTV project. They later released an album called No Quarter: Jimmy Page and Robert Plant Unledded, which featured some reworked Led Zeppelin songs, and embarked on a world tour the following year. This is said to be the beginning of a rift between the band members, as Jones was not even told of the reunion.

Led Zeppelin have collected many honours and awards throughout the course of their career. They were inducted into the Rock and Roll Hall of Fame in 1995, and the UK Music Hall of Fame in 2006. Among the band's awards are an American Music Award in 2005, and the Polar Music Prize in 2006. Led Zeppelin were the recipient of a Grammy Lifetime Achievement Award in 2005, and four of their recordings have been inducted into the Grammy Hall of Fame. They have been awarded five Diamond albums, as well as fourteen Multi-Platinum, four Platinum and one Gold album in the United States, while in the UK they have five Multi-Platinum, six Platinum, one Gold and four Silver albums. In addition to listing five of their albums among "the 500 Greatest Albums of All Time", Rolling Stone named Led Zeppelin the 14th-greatest Artist of all time in 2004.

In 1997, Atlantic released a single edit of "Whole Lotta Love" in the US and the UK, the only single the band released in their homeland, where it peaked at number 21. November 1997 saw the release of Led Zeppelin BBC Sessions, a two-disc set largely recorded in 1969 and 1971. Page and Plant released another album called Walking into Clarksdale in 1998, featuring all new material, but after disappointing sales the partnership dissolved before a planned Australian tour.

2003 saw the release of the triple live album How the West Was Won, and Led Zeppelin DVD, a six-hour chronological set of live footage that became the best-selling music DVD in history. In July 2007, Atlantic/Rhino and Warner Home Video announced three Zeppelin titles to be released that November: Mothership, a 24-track best-of spanning the band's career; a reissue of the Soundtrack The Song Remains the Same, including previously unreleased material; and a new DVD. Zeppelin also made their catalogue legally available for digital download, becoming one of the last major rock bands to do so.

In 2005, Page was appointed an Officer of the Order of the British Empire in recognition of his charity work, and in 2009 Plant was honoured as a Commander of the Order of the British Empire for his services to popular music. The band are ranked number one on VH1's 100 Greatest Artists of Hard Rock and Classic Rock's "50 best live acts of all time". They were named as the best Rock band in a poll by BBC Radio 2. They were awarded an Ivor Novello Award for "Outstanding Contribution to British Music" in 1977, as well as a "Lifetime Achievement Award" at the 42nd Annual Ivor Novello awards ceremony in 1997. The band were honoured at the 2008 MOJO Awards with the "Best Live Act" prize for their one-off reunion, and were described as the "greatest rock and roll band of all time". The three surviving members (Page, Plant, and Jones) were named as 2012 recipients of Kennedy Center Honors.

On 10 December 2007, Zeppelin reunited for the Ahmet Ertegun Tribute Concert at the O2 Arena in London, with Jason Bonham again taking his father's place on drums. According to Guinness World Records 2009, the show set a record for the "Highest Demand for Tickets for One Music Concert" as 20 million requests were submitted online. Critics praised the performance and there was widespread speculation about a full reunion. Page, Jones and Jason Bonham were reported to be willing to tour, and to be working on material for a new Zeppelin project. Plant continued his touring commitments with Alison Krauss, stating in September 2008 that he would not record or tour with the band. "I told them I was busy and they'd simply have to wait," he recalled in 2014. "I would come around eventually, which they were fine with – at least to my knowledge. But it turns out they weren't. And what's even more disheartening, Jimmy used it against me."

Jones and Page reportedly looked for a replacement for Plant; candidates including Steven Tyler of Aerosmith, and Myles Kennedy of Alter Bridge. However, in January 2009, it was confirmed that the project had been abandoned. "Getting the opportunity to play with Jimmy Page, John Paul Jones and Jason Bonham was pretty special," Kennedy recalled. "That is pretty much the zenith right there. That was a crazy, good experience. It's something I still think of often… It's so precious to me."

A film of the O2 performance, Celebration Day, premiered on 17 October 2012 and was released on DVD on 19 November. The film grossed $2 million in one night, and the live album peaked at number 4 and 9 in the UK and US, respectively. Following the film's premiere, Page revealed that he had been remastering the band's discography. The first wave of albums, Led Zeppelin, Led Zeppelin II, and Led Zeppelin III, were released on 2 June 2014. The second wave of albums, Led Zeppelin IV and Houses of the Holy, were released on 27 October 2014. Physical Graffiti was released on 23 February 2015, almost exactly forty years to the day after the original release. The fourth and final wave of studio album reissues, Presence, In Through the Out Door, and Coda, were released on 31 July 2015.

Coda – a collection of Zeppelin outtakes and unused tracks – was issued in November 1982. It included two tracks from the Royal Albert Hall in 1970, one each from the Led Zeppelin III and Houses of the Holy sessions, and three from the In Through the Out Door sessions. It also featured a 1976 Bonham drum instrumental with electronic effects added by Page, called "Bonzo's Montreux".

Led Zeppelin are widely considered to be one of the most successful, innovative, and influential bands in the history of rock music. Rock critic Mikal Gilmore said, "Led Zeppelin—talented, complex, grasping, beautiful and dangerous—made one of the most enduring bodies of composition and performance in twentieth-century music, despite everything they had to overpower, including themselves".

On 6 November 2015, the Mothership compilation was reissued using the band's newly remastered audio tracks. The reissuing campaign continued the next year with the re-release of BBC Sessions on 16 September 2016. The reissue contained a bonus disc with nine unreleased BBC recordings, including the heavily bootlegged but never officially released "Sunshine Woman."

To commemorate the band's 50th anniversary, Page, Plant and Jones announced an official illustrated book celebrating 50 years since the formation of the band. Also released for the celebration was a reissue of How The West Was Won on 23 March 2018, which includes the album's first pressing on vinyl.