Apparatus builder and cameraman 
From 1903 Froelich was a colleague of Oskar Messter, one of the advance guard of German cinema, for whom initially he worked on the construction of cinematographic equipment. As cameraman for Messter's weekly newsreels he filmed among many other things the aftermath of a train accident on the Berlin elevated railway on 28 September 1908, one of the worst transport disasters of the time.
Film director and producer 
Between 1912 and 1951 he made 77 films.
In 1913 Froelich made his directorial debut with Richard Wagner. In 1920 he founded his own production company, Froelich-Film GmbH, among the productions of which were Kabale und Liebe (1921), Die Brüder Karamasoff (1922), and Mutter und Kind (1924). During these years he often filmed with the actress Henny Porten, who made her screen debut in one of his earliest films, and with whom between 1926 and 1929 he shared ownership of a production company.
In 1929 Froelich made the first German sound film, Die Nacht gehört uns ("The Night Belongs To Us"). In 1930 he took over two glasshouses in Berlin-Tempelhof, which had been used as studios in the days of silent film, and had them converted to sound film studios. Here he produced many films, including Rolf Hansen's short film Das Schönheitsfleckchen (1936) ("The Beauty Spot"), the first German drama film in colour. In 1931 he was advisor, as "senior artistic director", to Leontine Sagan's famous boarding-school film and later lesbian classic, Mädchen in Uniform ("Girls in Uniform") (1931).
Some of the best-known of the films he made during this period were:
- 1934: Ich für dich, du für mich for the Reich Propaganda Directorate of the NSDAP
- 1938: Heimat
- 1940: Das Herz der Königin ("The Queen's Heart"), an anti-British historical film about Mary, Queen of Scots
- 1941: Der Gasmann, a propaganda film, in which Heinz Rühmann plays a gas-meter reader suspected of being a foreign spy
Culture politics 
Froelich became a member of the National Socialist Party in 1933 and took over the direction of the Gesamtverbandes der Filmherstellung und Filmverwertung ("Union of Film Manufacture and Film Evaluation"). In 1937 he was awarded a professorship and in 1939 was appointed president of the Reichsfilmkammer, an office which he retained until the end of the war in 1945. The Reichsfilmkammer was subordinate to the Reichskulturkammer, which as a National Socialist trade organisation regulated and controlled access to all artistic professions. He was one of the few filmmakers that received the title "Filmprofessor" from Goebbels.
After the end of the war 
After the end of the war Froelich was arrested and in 1948 de-Nazified. His studio had been badly damaged during the war and did not resume production. Only two more films were made under his direction before his death: Drei Mädchen spinnen and Stips.
Selected filmography 
- Heimat (1938)
- Cinzia Romani, Tainted Goddesses: Female Film Stars of the Third Reich p38 ISBN 0-9627613-1-1