Hammond and Cooper first worked together in the band A Primary Industry during the mid-1980s. Following the split of this band, they formed Ultramarine and released the album Folk in April 1990.
The duo's second album release, Every Man and Woman is a Star (1991) found critical acclaim, and Ultramarine was frequently seen at festivals such as Megadog and Glastonbury during the early to mid-1990s. A large part of the interest generated was due to the eclectic mix of samples and influences evident on Every Man and Woman the album is dedicated to Dewey Bunnell of the band America (band). Ultramarine were one of the only acts that was signed to Sire Records in the US through Giant Records instead of sister labels Warner Bros. or Reprise.
Their subsequent albums failed to reach the commercial heights of Every Man and Woman is a Star however. These included United Kingdoms (released August 1993, and featuring Robert Wyatt) and Bel Air (released August 1995). They also released the single "Hymn" (with David McAlmont) in 1996. Their last album was 1998’s A User’s Guide.
A remix album of Every Man and Woman is a Star entitled Companion (it was in reality an extended version of the previously available Nightfall in Sweetleaf) was released in May 2003 and collected various early, alternative, unreleased or live versions from 1990 to 1993. Remixes of tracks were by various artists including Spooky, Sweet Exorcist and Coco Steel.