Roberts formed the band that was eventually known as William in 1993. The band's name was changed to Northstar in 1996. Although the band gained some notice in independent rock circles, they couldn't break through to a national audience, and broke up in 1999 after failing to release an album. Roberts' bandmate George Donoso went on to significant success in indie rock circles with The Dears, but Roberts struggled for several years afterward.
After disbanding Northstar in 1999, Roberts promptly recorded the full-length and now very collectible independent debut Brother Down at home. In 2001, Roberts recorded and released a six-song EP, The Inhuman Condition, independently. The EP sold slowly at first, but following a re-release of the EP in the summer of 2002 on MapleMusic Recordings, his first single "Brother Down" became one of the biggest Canadian hits of the year, and the second single, "Don't Walk Away Eileen", followed suit in the fall.
Roberts then signed to Universal Music and released his full-length major label debut, We Were Born in a Flame, in June 2003. That album's singles, "Where Have All the Good People Gone?" and "Hard Road", received a large amount of success, though mainly just in Canada.
The band's second album, Chemical City, was released in Canada in April 2006. In Canada, the first single was "The Gate", which quickly shot to number one on Canadian rock radio. The second single in Canada was "Bridge to Nowhere". "With a Bullet", the third song used to promote the album on Canadian radio, received little attention and no video was made for it.
Roberts' most recent album, Love at the End of the World, was released in May 2008. It debuted at the number one position on the Canadian album chart, a first for Roberts. The lead single, "Them Kids", debuted on iTunes on March 4, 2008.