The Australian Naval and Military Expeditionary Force (AN&MEF) began forming following a request by the British government on 6 August 1914.

[5] Another battalion of militia from the Queensland-based Kennedy Regiment, which had been hurriedly dispatched to garrison Thursday Island, also contributed 500 volunteers to the force.

[Note 1][8] The soldiers from the Kennedy Regiment were also left in Port Moresby as Holmes felt that they were not trained or equipped well enough to be committed to the fighting that was expected.

[2][9] Off the eastern tip of New Guinea, the Berrima rendezvoused with Australia and the light cruiser HMAS Sydney plus some destroyers.

Sydney and the destroyer HMAS Warrego landed small parties of naval reservists at the settlements of Kabakaul and the German gubernatorial capital Herbertshöhe (now Kokopo) on Neu-Pommern (now New Britain), south-east of Rabaul.

A small 25-man force of naval reservists was subsequently landed at Kabakaul Bay and proceeded inland to capture the radio station believed to be in operation at Bita Paka, 7 kilometres (4.3 mi) to the south.

The following afternoon, despite the fact that the German governor had not surrendered the territory, a ceremony was carried out to signal the British occupation of New Britain.

[11] Regardless, the Australians had prevailed not least of all because of their unexpected ability to fight close terrain, while the outflanking of the German positions had unnerved their opponents.

[20] On 9 January 1915,[21] Holmes handed over command of the AN&MEF to Brigadier General Sir Samuel Pethebridge, the former Secretary of the Department of Defence.

[25] Following the end of hostilities in November 1918 the role of the AN&MEF in the former German colonies in New Guinea had become primarily one of civil administration, although it continued to provide a garrison for the next two and a half years.

[20] Although the AN&MEF had seen no further action following the initial seizure of the colony, in the years that followed the climate and a range of tropical diseases, such as malaria, had resulted in dozens of fatalities before the deployment concluded.