Led Zeppelin II

The band made the album while touring in 1969, recording and mixing each song separately in whatever studio was near. Engineers included George Chkiantz, Chris Huston, Andy Johns and Eddie Kramer, and Page and Kramer mixed for two days at A&R in New York. Plant later criticized the scattered process.

The recording locations included Olympic and Morgan in London, A&M, Quantum, Sunset, Mirror Sound and Mystic in Los Angeles, Ardent in Memphis, A&R, Juggy Sound, Groove and Mayfair in New York, and a Vancouver studio credited as "a hut". Chkiantz engineered Whole Lotta Love and What Is and What Should Never Be at Olympic, Huston did The Lemon Song and Moby Dick at Mystic in Los Angeles, Andy Johns did Thank You and Living Loving Maid at Morgan, and Kramer did Heartbreaker, Ramble On and Bring It On Home in New York. Kramer later said the Whole Lotta Love mix was Page and himself flying around a small console twiddling every knob. These were Plant's first songwriting credits, because the CBS contract had barred them on the first album.

Reviews were divided. Rolling Stone's John Mendelsohn wrote that it seemed like one especially heavy song stretched over two sides, and Robert Christgau said all the songs sound alike. Pitchfork's Mark Richardson, writing on the 2014 reissue, said it sounds as thrilling as ever. It was number one in the US for seven weeks, and also in the UK, Canada and Australia, and is certified 12x Platinum in the US. Rolling Stone placed it 123rd on its 2020 list.

Advance orders were 400,000. The album knocked The Beatles' Abbey Road off the top of the US chart twice, stayed at number one for seven weeks, and spent 138 weeks on the UK chart after reaching the top there in February 1970. The RIAA certified it gold on 10 November 1969, 5x Platinum in 1990 and 12x Platinum on 14 November 1999, and the 2014 reissue reached number 9 on Billboard. David Juniper's cover, built from a photograph of the Flying Circus squadron led by the Red Baron, earned a Grammy nomination for Best Recording Package. The Heartbreaker solo has been cited as an influence on Eddie Van Halen's tapping and on Steve Vai. Rolling Stone ranked the album 75th in 2003 and 79th in 2012.