Marcus Mumford single-handedly organized a band and arranged performances to get their music out there. Mumford formed Mumford & Sons in December 2007 with multi-instrumentalists Ben Lovett (vocals, keyboards, accordion, drums), "Country" Winston Marshall (vocals, banjo, dobro, guitar), and Ted Dwane (vocals, string bass, drums, guitar). They would later be known as one of the "West London folk scenes", but Mumford insisted they were neither folk nor a scene, but rather a non-exclusive community.

In 2008, the band signed with management company Everybody's which delivered them to A&R at Island, Louis Bloom. With no album yet, the band opened for other music acts around U.K., U.S. and Australia, performing materials which would later become "Sigh No More". As they gained fans, it was time to make a record. Assisted by Markus Dravs, the band began crafting their debut album, using their own money to avoid artistic and technical compromises. They eventually signed a licensing deal with several labels in 2009 and the debut album was released in October that year with "Little Lion Man" as lead single.

Mumford and Sons received wider exposure with "Little Lion Man", which was performed throughout early 2010 as promotional single. They were especially famous in Australia, having won an ARIA Music Award for Most Popular International Artist in 2010. Their work was also recognized Stateside with them taking Grammy nominations for Best New Artist and Best Rock Song ("Little Lion Man") in the same year. They did not go home with any of the trophy but left impression on the audience by performing "The Cave" at the prestigious ceremony. As a result, the album soared to number 2 on Billboard Hot 200 chart a week after the performance.

Their popularity rose higher in 2011 as they conquered the U.K. market and toured the U.S. In the middle of the euphoria, the band took time to write for the next album in Nashville, Tennessee. Several of the new tracks were performed during their shows including at the Glastonbury Festival in June 2011. The album was initially planned to be released in late 2011 but the band was so occupied with tours that only on September 24, 2012 were they ready to put it in stores. "Babel" was led by the single "I Will Wait". The album debuted at number one on both Billboard 200 and U.K. Albums chart upon its release. In fact, "Babel" was the biggest selling debut of any album in 2012 in the U.S., selling 600,000 in its first week.

The band then spent the rest of 2012 and 2013 playing live gigs to promote the record before announcing in late 2013 that they'd take a break from music after wrapping up their "Babel" tour. In early 2014, the group's frontman Mumford revealed what he and his pals were doing while they were on hiatus. He said he told people the group had broken up. "Everyone keeps asking if we've broken up as a band, which I love... So I keep saying 'yes,' and then we can have a big come back tour next year," he told U.K. radio station XFM.

He also revealed that banjo player Winston Marshall "went to Nashville and set up a band, played six gigs, recorded a live show and then they broke up, citing artistic differences at the end of the night, after playing six gigs in one night."

"Apparently they were rubbish, apparently they were genuinely rubbish. But they're really proud of it, because they love that kind of thing," he explained.

Mumford and Co. finally ended their hiatus in early 2015. They announced in January they'd return to headline the 2015 Bonnaroo Music Festival. In February, they confirmed they'd be performing at the Reading & Leeds Festival. In March, they announced that their third studio album would be entitled "Wilder Mind" and would be released 4 May 2015. It's led by single "Believe" which was released to radio stations on 9 March 2015 and then debuted at No. 17 on Billboard Hot 100.