Following the outbreak of the First World War, Grossberg enlisted in the military on 1 November 1914. In August 1915, he was promoted to the rank of reserve lieutenant and deployed to the Western Front in France. He was buried alive in a trench, suffering physical and psychological trauma as a result, requiring repeated treatment in 1916 and 1917. The resulting depression-like conditions accompanied him for the rest of his life.
Grossberg continued to draw during his military service. Two sketchbooks from 1915 and 1916 are presented in the exhibition. On the one hand, these sketches reveal some of Grossberg's exact locations of deployment; on the other hand, they contain small everyday scenes that Grossberg captured in a caricature-like manner.
Grossberg remained in military service until 23 December 1918. Just a few weeks later, on 27 January 1919, he applied to study painting at the Großherzoglich-Sächsische Hochschule für Bildende Kunst (Royal Saxon Academy of Fine Arts) in Weimar.
