Mezue ahịrịokwu na-esonụ: Mgbe mmeri nke ndị agha Serbia na
Agha nke Kolubara na Disemba 1914, agha ndị Serbia hụrụ udo ruo mmalite oge mgbụsị akwụkwọ nke 1915. N'okpuru iwu nke Field Marshal August von Mackensen, ndị agha Austro-Hungarian Balkan Army, ndị agha German nke 11 na osimiri mmiri na Danube na Sava malitere mwakpo na 6 Ọktọba 1915, mwakpo kachasị ukwuu megide Serbia. Ka ọ na-erule Septemba 1915, n'agbanyeghị oke ịchụ àjà nke ndị agha Serbia, ndị agha Austro-Hungarian Balkan, mgbe ha gafere osimiri Sava na Drina na ndị agha German nke 11 mgbe ha gafesịrị Danube, weghaara Belgrade, Smederevo, Požarevac na Golubac, na-eke akwa akwa dị na ndịda nke Sava na Danube, ma na-amanye ndị agha Serbia ịlaghachi na ndịda Serbia.