The battalion was raised as part of the all volunteer Australian Imperial Force (AIF) within three weeks of the declaration of war in August 1914, and left Australia just two months later. Part of the 3rd Brigade, 1st Division it was formed from recruits from Tasmania, South Australia and Western Australia. Under the command of Lieutenant Colonel Lancelot Clarke, the battalion proceeded to Egypt on HMAT A2 Geelong, arriving on 2 December. A period of training in the desert followed to prepare the Australian forces for their eventual transfer to Europe, but in late April they were committed to the Gallipoli Campaign. The 3rd Brigade was the covering force for the Anzac landing on 25 April 1915, and went ashore at around 4.30 am. During the early fighting on the first, the battalion's commanding officer was killed by a sniper.