Cer Kolubara anti-aircraft warfare ground-to-air medical evacuation Serbia Russia
Beginning on 12 August, the Austrian and Serbs clashed at the battles of the Cer and Kolubara; over the next two weeks, Austrian attacks were repulsed with heavy losses, dashing their hopes of a swift victory and marking the first major Allied victories of the war. As a result, Austria had to keep sizeable forces on the Serbian front, weakening its efforts against Russia. Serbia's defeat of the 1914 invasion has been called one of the major upset victories of the twentieth century. In spring 1915, the campaign saw the first use of anti-aircraft warfare after an Austrian plane was shot down with ground-to-air fire, as well as the first medical evacuation by the Serbian army in autumn 1915.
