Reinhardt was born in Berlin, the son of the Austrian theater director Max Reinhardt (until 1904: Max Goldmann), manager of the Deutsches Theater, and his first wife Else Heims. Gottfried attended the Französisches Gymnasium Berlin and began his career as an actor and director at his father's stage.
In 1932, he went on a study visit to the US, where he remained after the NaziMachtergreifung in Germany on 30 January 1933. In Hollywood, he became assistant director of Ernst Lubitsch, later a production assistant at the Metro-Goldwyn-Mayer studios, contributing to the making of the 1938 film The Great Waltz. In 1941 he produced Two-Faced Woman starring Greta Garbo in her final film role. A naturalized American, he served in the United States Army in World War II.