The group started around 1984, two years before the usual start date golden age of old school rap began in 1986. Many believe that without the group's primary producer, Ced-Gee, the sound and samples, mostly James Brown, wouldn't have been as prominent. Their break-out single was Funky/Mentally Mad. It was released in 1987 and put the foursome on the map. This led to the release of the album, Critical Beatdown.
Although the Ultramagnetic MCs released a new school classic in 1988, "Critical Breakdown," with typical James Brown samples - they disappeared after that for several years, to return on Mercury Records in 1992, with the album "Funk Your Head Up". 1993's "The Four Horsemen" was considered extremely strange though still brilliant. That was the last album the Ultramagnetic MCs released.
There were several bootleg and compilation albums to follow, many with outtakes or older material not released ( such as "The B-Sides Companion").
The Ultramagnetic MC's launched the career of "Bronx Nigga" (Tim Dog) who brought out the very successful single "Fuck Compton". Kool Keith and Tim Dog reunited on the semi-Ultramagnetic MCs reunion album, "Big Time". Kool Keith went on to record many solo CDs, including one under the "Dr. Octagon" monicker. His abstract rhymes influenced many rappers, including Pharaohe Monch from Organized Konfusion.