Roland Emmerich is a German-American film director, who is best known for making big-budget action films with incredible special effects with Dean Devlin. The two of them wrote the original Stargate movie, which Emmerich directed.
Stargate was originally planned as the first in a film franchise. However, the pair became involved in other projects (Independence Day, Godzilla, etc.), and abandoned Stargate. Emmerich and Devlin do not consider Stargate SG-1 a valid continuation of their film.
Emmerich's films have grossed $2.7 billion worldwide, more than those of any European-born director and making him the country's 14th-highest grossing director of all time.