Didier David, better known as Cromwell, was a member of Asylum, a group of young artists and scenarists in the 1980's. He cooperated on 'Mondes Engloutis', an animated series for France 2. A comics version appeared at Casterman in 1985 and 1986. At the same time, Cromwell created the 'Sergei Wladei' series, together with fellow artists Riff Reb's and Edith and scenarist Ralph. In 1988, Cromwell worked for Circus. A year later, he created the western 'Minettos Desperedos' with scenarist Joe Ruffner at GlÚnat publishers, which lasted for three episodes until 1992. After some contributions to Flag and Racaille! and the collective album '7 Histoires de Pirates', Cromwell and Ruffner took on the saga 'Anita Bomba' at Casterman between 1994 and 1997. In 2003, he teamed up with Riff Reb's again to create 'Tenu par les Couilles', a new episode of 'Sergei Wladei' scripted by Eric Gratien (the real name of Joe Ruffner).