The Military Administration in Serbia was established on occupied Yugoslav territory in April 1941 , following the invasion of the country . On 30 April a pro-German Serbian administration was formed under Milan Aćimović to serve as a civil administration in the military occupation zone . A joint Partisan and Chetnik uprising in late 1941 became a serious concern for the Germans , as most of their forces were deployed to Russia ; only three divisions were in the country . On 13 August 546 Serbs , including some of the country 's prominent and influential leaders , issued an appeal to the Serbian nation that condemned the Partisan and royalist resistance as unpatriotic . Two weeks after the appeal , with the Partisan and royalist insurgency beginning to gain momentum , 75 prominent Serbs convened a meeting in Belgrade and formed a Government of National Salvation under Serbian General Milan Nedić to replace the existing Serbian administration . The Germans were short of police and military forces in Serbia , and came to rely on poorly armed Serbian formations , the Serbian State Guard and Serbian Volunteer Corps , to maintain order . These forces , however , were not able to contain the resistance , and for the most of the war large parts of Serbia were under control of the Partisans or Chetniks ( the two resistance movements soon became mutually-hostile ) . The Government of National Salvation , imbued with few powers upon formation , saw its functions further decreased and taken over by the Wehrmacht occupation authorities as the war progressed . After the initial mass revolts , the German authorities instituted an extreme regime of reprisals , proclaiming that 100 civilians would be executed for every German soldier killed , and 50 for each one wounded . These measures were actually implemented on more than one occasion : large-scale shootings took place in the Serbian towns of Kraljevo and Kragujevac during October 1941
Kragujevac
Kragujevac massacre
Axis powers