The 2nd Brigade was a brigade-sized infantry unit of the Australian Army. Formed in 1903 as a militia formation based in Victoria, the brigade later served during the First World War as part of the Australian Imperial Force, allocated to the 1st Division. During the war, the 2nd Brigade took part in the fighting at Gallipoli, including the Battle of Krithia where it lost almost a third of its strength. Later they took part in the Battle of Lone Pine before being withdrawn back to Egypt in December 1915. Following this the brigade was transferred to the Western Front in France and Belgium where, between March 1916 and the armistice in November 1918, they took part in most of the major Allied operations.