their beachheads at Buna, Gona and Sanananda on the Papuan north coast. Within sources dealing with the fighting in New Guinea, Maroubra Force remains an enigmatic entity. While authors such as Eustace Keogh, Brune and McCarthy largely fall silent on the formation after the Battle of Ioribaiwa in mid-September, Chant states that Maroubra Force later participated in the fighting around Gona. Nevertheless, the last mention of the Maroubra codename in the New Guinea Force Headquarters War Diary appears on 28 October. During the fighting around Buna and Gona, between in November 1942 and January 1943, Porter's 30th Brigade, which had been withdrawn earlier, reinforced elements of the 7th Division – the 18th and 25th Brigades – and eventually took part in the reduction of the Japanese beachhead there. The 21st Brigade also took part in the fighting around the Japanese beachheads, suffering heavy casualties. Commanders An ad hoc command, Maroubra Force was variously commanded by the senior officer in the forward area of the battle, which meant that command changed hands on a number of occasions. Major (later Lieutenant Colonel) Allan Cameron took command of the formation during the fighting around Kokoda after the death of Lieutenant Colonel William Owen, while Lieutenant Colonel Ralph Honner filled the role during the brief period between Kokoda and Isurava. Brigadier Selwyn Porter (30th Brigade) and Brigadier Arnold Potts (21st Brigade) also held the position. Potts was later relieved of his command in controversial circumstances following actions at Isurava, Eora Creek and Templeton's Crossing, and Efogi. He was replaced by Porter in early September prior to the Battle of Ioribaiwa. Maroubra Force then passed to Brigadier Kenneth Eather, commander of the 25th Brigade, for the fighting around Ioribaiwa and the counter-offensive that followed. Strength and casualties According to Chant, "at its peak strength, Maroubra Force consisted of the 39th and 53rd Infantry Battalions, and the 21st Brigade (2/14th, 2/16th and 2/27th Infantry Battalions). The 53rd Militia Battalion saw action briefly during the Battle of Isurava but was defeated and subsequently withdrew greatly demoralised, especially after the commanding officer and many senior officers of the 53rd were killed in action". Williams provides a contrasting assessment, though, stating that just prior the fighting around Ioribaiwa, following the arrival of the 25th Brigade, Maroubra Force totaled 2,957 personnel – up from 2,292 at the start of Isurava – with a combined headquarters from both the 21st and