At the outbreak of war, the RAN stood at 3,800 personnel and consisted of sixteen ships, including the battlecruiser Australia, the light cruisers Sydney and Melbourne, the destroyers Parramatta, Yarra, and Warrego, and the submarines and .
On 9 November 1914, the German light cruiser attacked the Allied radio and telegraph station at Direction Island in the Cocos (Keeling) Islands.