In September 1919 he returned to his job with Kosterlitz. Early in 1920 he switched to the Darmstädter und Nationalbank, employed in the bank's Berlin branch. In his spare time he worked voluntarily for a prisoner of war organisation. Kurt Großmann had emerged from the British PoW camp as a committed pacifist and, in the face of significant opposition from populist elements, he took a lead in the international honouring of war victims. In Berlin, on "Totensonntag" ('Sunday of the Dead'), in 1921 he organised a "Feier zu Ehren der Toten des Weltkrieges" ('Celebration of the World War dead'). Reactions were mixed, but when the event was repeated in 1922 participants included the president of the Reichstag (parliament), Paul Löbe. Großmann's involvement with the German League for Human Rights dates back to this period. A few years later, on 11 November 1928, Großmann teamed up with Stephan Fingal to stage the only formal commemoration in Germany of the 1918 Armistice of the Weimar period.