Papua and New Guinea had been the Australian 8th Military District under command of Morris. On 9 April 1942, it was formed into New Guinea Force, with Morris promoted major general. As events escalated and the forces involved increased, Rowell arrived from Australia with HQ I Corps, taking command of the force on 12 August 1942. Morris was moved to command the Australian New Guinea Administrative Unit (ANGAU). At about this time, 7th Division was deploying to New Guinea and responsibility for the immediate defence of Port Moresby, including Maroubra Force and the Kokoda Track operation was devolved to divisional headquarters under Allan.