1. The social disruptions and economic shortages of the Weimar Republic gave rise to new techniques and styles in German film-making dubbed Expressionism.

2. Unable to afford large casts or sets, directors looked for different cinematic and production techniques to render style, character and emotion.

3. Expressionist film-makers like F. W. Murnau and Fritz Lang were also concerned with darker storylines and themes, including horror and crime.

4. Expressionist directors developed innovative techniques, such as new uses for light, contrast, camera angles and movement.

5. These directors and their innovations came to influence the wealthier and more prolific film studios in Hollywood.

Source: https://alphahistory.com/weimarrepublic/weimar-cinema/#:~:text=1.,render%20style%2C%20character%20and%20emotion.