Leopold Hilgarth (1895–1945) and Ignatz Schuhmann (1909–1945) belonged to a resistance group in Alkoven, the location of the Hartheim killing centre, as of 1943. In February 1943, the following words were found on its walls: »Austrians! Hitler started the war – Hitler's downfall will end it!«. A little later came, a letter was sent to the NSDAP Ortsgruppenleiter (»Local Group Leader«) in Alkoven demanding »retaliation« for the »mass murder of innocent people« in Hartheim, too.

Hilgarth and Schuhmann made even more leaflets until the Gestapo arrested them in June 1944. Two months later, the Volksgerichtshof (»People's Court«) of Vienna accused the two men of treason. They were sentenced to death and executed on 9 January 1945.