His early illustrations contained dream-like abstractions, while his later work was characterised by motifs such as peasants, warriors, and other naked human figures in natural settings.

By 1900 he was one of the best known painters in Germany, and had come under the influence of writers such as Arthur Moeller van den Bruck, Heinrich and Julius Hart, and the anti-materialist garden city and Wandervogel movements.

[3] In 1912 he designed a famous poster for a congress on "biological hygiene" in Hamburg, showing a man in the process of breaking his bonds and rising up to the stars.

Fidus perceived the blood and soil (Blut und Boden) idea in Nazism to fit with his veneration of nature and the human spirit, so he joined the party in 1932.

Another large archive of Fidus materials (including artworks, diaries, correspondence, and photographs) is held by the Jack Daulton Collection in Los Altos Hills, California.