After her younger son Peter had fallen in 1914 as a volunteer in the First World War, Käthe Kollwitz underwent a painful change of heart and became a pacifist.
    
    
        Peter, […] they all devoted their lives to the idea of patriotism. 
The young men in England, Russia and France did the same. 
The result was […] an impoverished Europe robbed it of its most beautiful people. Was the youth in all these countries deceived?«
Käthe Kollwitz, Diaries, 11 October 1917
     
 
In 1918 the artist challenged Richard Dehmel’s appeal for a final push to win the war in an open letter that was published in Vorwärts (28 Oct) and two days later in Vossische Zeitung (30 Oct): 
    
    
        Enough people have died! No more people must fall! I invoke a greater poet than Richard Dehmel [Goethe] who said: ›Seed for sowing should not be milled‹.«
Käthe Kollwitz, reaction to Richard Dehmel’s appeal, 
28 October 1918
     
 
Alongside her woodcut series »War«, the artist already created anti-war prints and drawings during the First World War. After Hitler had come to power and a new world war was looming, she returned to this field of topics above all with sculptural works. As Käthe Kollwitz’ works were unofficially banned from being exhibited in public from 1935 onwards, these works failed to reach a larger public.
As a result of the outbreak of war, she again used the quote »Seed for sowing should not be milled« in a lithograph. In her diary entries of 1941 she referred to this quote as her legacy.
    
       
       
            Käthe Kollwitz, In Memory of Ludwig Frank, rejected second version, 1914, crayon lithograph (transfer of an unknown drawing on ribbed laid paper), Kn 131
         
     
    
    
       
        
            Käthe Kollwitz, Self-portrait with her Son Hans, 1914-1916, black crayon on Ingres paper, NT 732
         
     
    
    
     
        
            Käthe Kollwitz, Two dead Persons, 1920, woodcut, Kn 158 IV
         
     
 
    
       
       
            Käthe Kollwitz, Aerial Bomb, 1924/1925, brush and black ink, NT 960
         
     
    
    
       
        
            Käthe Kollwitz, Tower of Mothers, 1937/1938, bronze, Seeler 35 II.B.1
         
     
    
    
     
        
            Käthe Kollwitz, Pietà (Mother with dead Son), 1937-1939, bronze, Seeler 37 II.B.1
         
     
 
    
       
       
            Käthe Kollwitz, »Seed for sowing should not be milled«, 1941, crayon lithograph, Kn 274