Born in Warsaw in the 1930's to a simple Jewish tailor and his wife, Rachael Berkowitz saw her father gunned down by the Nazi's. She then grew up in a concentration camp - her mind becoming more twisted as she did so - until she eventually believed that the Nazi "Final Solution" idea was correct.
Escaping to the U.S. at the end of the war, this brilliant young woman received a Phd at the age of 18. She unlocked the secrets of the Unified Field Theory several years later, enabling her to tap into the primal forces of the universe. This in turn enabled her to reshape herself into the elemental being known as Blackstarr.
Now possessed of extraordinary powers, Blackstarr began a political campaign of racist rhetoric designed to stir up anti-semetic sentiment among the people. When a riot broke out in Chicago, Supergirl arrived on the scene to quell any threat to public order. Realising she now faced the one opponent who could thwart her plans, Blackstarr sought to destroy the girl of steel, but their repeated battles only led to Blackstarr's own demise when she appeared to be torn apart by the conflicting gravitational fields of two black holes.
Without their leader, BlackStarr's fascist followers soon disbanded, dying with her monstrous dream. Blackstarr survived and later appeared as a recruit for a newly led Suicide Squad. Blackstarr was a member of the Sgt. Rock led Suicide Squad and was included as a one time member going on one mission.