Since the First World War, the writer and poet had also been immersing himself in painting. From his self-taught beginnings, which helped him to overcome an existential crisis, he produced a significant painterly oeuvre in the shape of some 3,000 watercolours that capture the beauty of Tessin - Hesse's chosen home from 1919 until his death in 1962 - in glowing shades.
In 1916, Hesse undergoes psychoanalysis in Sonnmatt near Lucerne. His therapist, Dr. J. B. Lang, urges him to describe his dreams in visual form. Hesse paints his first pictures in Berne and the environs of Locarno in Tessin.
In 1917, Hesse turns his attentions to the self-portrait.
Further artistic efforts follow in 1918, also giving rise to the first texts and illustrations for Wanderung (published 1920). To aid the prisoners of war welfare organization he had set up in Berne in 1916, Hesse sells his first self-illustrated cycles of poems. 1919: Hesse illustrates his fairy-tale Der schwere Weg, and paints watercolours to accompany the Gedichte des Malers. The first exhibition of Hesse's watercolours is staged in the Kunsthalle Basel in 1920, and in 1920 early reproductions are also published in the periodical Wieland, Munich. In 1921, the portfolio Elf Aquarelle aus dem Tessin appears. In 1922, an exhibition of watercolours together with works by Emil Nolde is put on in Winterthur. Hesse writes and paints the illustrated fairy-tale Piktors Verwandlung for Ruth Wenger. 1925 sees the publication of Die Lugenesiche Landschaft by Josef Ponten, and 1926 his story Die letzte Reise, both containing colour reproductions of watercolours by Hesse. There is an exhibition featuring 50 watercolours in Berlin and 100 watercolours in Dresden.
In 1955, the first volume of Aquarelle aus dem Tessin and a series of art postcards based on watercolours by Hermann Hesse are published. In 1957, to mark his 80th birthday, an exhibition of Hesse watercolours is staged at the Schiller-Nationalmuseum in Marbach. After Hesse's death (1962), worldwide exhibitions of his watercolours are put on in major cities such as Tokyo (1976 and 1996), Paris (1977), New York and Montreal (1980), San Francisco and Chicago (1981), Madrid (1985), Luxembourg (1987), Hamburg (1992) and Sapporo (1995).