Grohl originally asked Novoselic to join Foo Fighters as a full time band member, but he declined stating people would refer to it as "the second Nirvana".
Novoselic's first experience with Foo Fighters was participating in the encore of their show on August 29, 1997 at Memorial Stadium as part of the Bumbershoot festival, where he played bass for the band's covers of "Purple Rain" and "Communication Breakdown". In January 2002, Novoselic performed backing vocals for a non-album track titled "Walking a Line", later released on a special edition of the band's album One by One.
Later, during the encore of Foo Fighters' secret show at Paladino's in Tarzana, California on December 22, 2010, the band, with Grohl on drums was joined onstage by Novoselic and the band's live guitarist Pat Smear for a version of Nirvana's "Marigold" a 1992 Grohl original, which was a B-side on Nirvana's "Heart-Shaped Box", the first single from In Utero. Novoselic also recorded bass and accordion on the song "I Should Have Known", appearing on Foo Fighters' seventh studio album called Wasting Light, released on April 12, 2011.
In 1986, friends Billie Joe Armstrong and Mike Dirnt, 14 years old at the time, formed a band called Sweet Children. The group's first live performance took place on October 17, 1987, at Rod's Hickory Pit in Vallejo, California. In 1988, Armstrong and Dirnt began working with former Isocracy drummer John Kiffmeyer, also known as "Al Sobrante". As said in the film Punk's Not Dead, Armstrong cites the band Operation Ivy (which featured Tim Armstrong and Matt Freeman of Rancid) as a major influence, and a group that inspired him to form a band.
In 1988, Larry Livermore, owner of Lookout! Records, saw the band play an early show and signed the group to his label. In 1989, the band recorded its debut extended play, 1,000 Hours. Before 1,000 Hours was released, the group dropped the name Sweet Children; according to Livermore, this was done to avoid confusion with another local band Sweet Baby. The band adopted the name Green Day, due to the members' fondness for cannabis.
Lookout! released Green Day's debut studio album, 39/Smooth in early 1990. Green Day recorded two extended plays later that year, Slappy and Sweet Children, the latter of which included older songs that the band had recorded for the Minneapolis independent record label Skene! Records. In 1991, Lookout! Records re-released 39/Smooth under the name 1,039/Smoothed Out Slappy Hours, and added the songs from the band's first two EPs, Slappy, and 1,000 Hours. In late 1990, shortly after the band's first nationwide tour, Kiffmeyer left the East Bay area to attend Humboldt State University in Arcata, California. The Lookouts drummer Tr Cool began filling in as a temporary replacement and later Cool's position as Green Day's drummer became permanent, which Kiffmeyer "graciously accepted". The band went on tour for most of 1992 and 1993, and played a number of shows overseas in Europe. The band's second studio album Kerplunk sold 50,000 copies in the U.S.