Serbian campaign
when was the Austrian invasion?
World War I
Austria invaded and fought the Serbian army at the Battle of Cer and Battle of Kolubara beginning on 12 August. Over the next two weeks, Austrian attacks were thrown back with heavy losses, which marked the first major Allied victories of the war and dashed Austro-Hungarian hopes of a swift victory. As a result, Austria had to keep sizable forces on the Serbian front, weakening its efforts against Russia. Serbia's defeat of the Austro-Hungarian invasion of 1914 counts among the major upset victories of the last century. This campaign had the youngest known soldier of World War I. Momčilo Gavrić, born in Trbušnica, joined the 6th Artillery Division of the Serbian Army when he was 8 years old, after Austro-Hungarian troops killed his parents, grandmother, and seven of his siblings in August 1914. At the age of 10 he was promoted to Corporal, and at the age of 11 he became a Lance Sergeant.