Mos Def began his music career with the short-lived group Urban ThermoDynamics with his younger brother DCQ, and his younger sister Ces. In 1996, he emerged as a solo artist working with De La Soul and da Bush Babees, before releasing his own first single on Rawkus, Universal Magnetic, which was a huge underground hit.

After signing with Rawkus Records, Mos Def and Talib Kweli formed the group Black Star, and released a full length album under the name, Mos Def and Talib Kweli are Black Star, the album was released in 1998, and featured Hi-Tek producing most of the tracks.

Mos Def released his solo debut, Black on Both Sides, in 1999. Mos was also featured on Rawkus influential Lyricist Lounge and Soundbombing series compilations.