Formed in New York in 2008, Fun. is comprised of members who were previously in other bands, including Jack Antonoff (Steel Train), Andrew Dost (Anathallo) and frontman Nate Reuss (the Format). The trio began collaborating in Antonoff's parents' living room, fusing pop  and original melodic hooks to create their signature sound. In 2009 Fun. released their debut album, Aim And Ignite, which peaked at No. 71 on the Billboard 200.

In 2012 the trio released their sophomore outing, Some Nights, which was co-produced by GRAMMY winner Jeff Bhasker (Beyoncé, Jay-Z, Kanye West). Spanning pop, rock and hip-hop, Some Nights climbed to No. 3 on the Billboard 200 on the strength of the band's No. 1 hit "We Are Young" featuring Janelle Monáe. In addition to being the first-ever single to log more than six weeks with digital sales of 300,000 units or more, "We Are Young" sold more than 5 million units, making it the third biggest-selling song of 2012.

Fun.  garnered six nominations for the 55th Annual GRAMMY Awards, including Best New Artist and Record Of The Year and Song Of The Year for "We Are Young."