The Battle of Cer, initiated on August 15, 1914, was a crucial military engagement in the early stages of World War I, taking place in Serbia. Serbian forces faced the Austro-Hungarian army, which sought to expand its influence and dominate the Balkans. Led by General Stepa Stepanović, the Serbian army expertly utilized the mountainous terrain to their advantage, employing guerrilla tactics that caught the Austro-Hungarians off-guard.

The battle unfolded over the course of ten days, during which the Serbians executed strategic maneuvers that led to significant Austro-Hungarian casualties. The successful Serbian defense culminated in the Austro-Hungarian retreat, marking this battle as the first major Allied victory of the war. The significance of Cer lay not only in the military triumph but also in the psychological boost it provided to Serbia and the Allies, illustrating the possibility of successful coordination between the various nations involved in the conflict.

The battle set a precedent for future engagements and laid the groundwork for further Serbian resistance. Its outcome was celebrated not merely as a tactical victory but as an affirmation of Serbian independence and resilience in the face of a formidable adversary. This success turned public sentiment in Serbia largely in favor of the war effort, as it fueled hopes for eventual liberation from Austro-Hungarian rule and fostered national pride among Serbs.