Born in Lyss, Canton of Bern, he obtained his early education in Biel, where he experienced both German and French languages and cultures.

Studying with Eduard Fischer at the University of Bern, Gäumann received his PhD in 1917 for his research on Peronospora, a genus of water molds.

After travels and study in Sweden, the United States, and the East Indies, Gäumann worked as a plant pathologist in Buitenzorg, Java, from 1919 to 1922, and then as a botanist in Zurich for several years.

[2] Gäumann had diverse research interests, including plant pathology, soil algae, rust fungi, and fungal evolution.

[1] Other works that were well-received included his 1952 The Fungi–A Description of their Morphological Features and Evolutionary Development and his 1959 monograph Die Rostpilze Mitteleuropas (Rust Fungi of Middle Europe).