Maroubra Force South Seas Detachment The Battle of Ioribaiwa took place between 14 and 16 September 1942, during the Kokoda Track campaign in Papua during the Second World War.

Involving forces from Australia, the United States, and Japan, the fighting centred on a high feature known as Ioribaiwa Ridge, south of Ofi Creek on the Kokoda Track, in the Territory of Papua.

It was the last of three defensive battles fought by the Australians along the Kokoda Track to halt the Japanese advance from the north coast of Papua towards Port Moresby.

On 21 July 1942, Japanese forces landed on the northern Papuan coast around Buna and Gona, as part of a plan to capture the strategically important town of Port Moresby via an overland advance along the Kokoda Track, following an unsuccessful seaborne attempt during the Battle of the Coral Sea in May 1942.

Kokoda fell in early August,[3] and this was followed by heavy fighting around Isurava later in the month as the veteran 21st Brigade reinforced the Militia troops that had been holding the line to that point.

[6] Situated south of Ofi Creek, the ridge was, according to authors Craig Collie and Hajime Marutani the "second-last razorback ridgeline before the Papuan capital".

By 11 September, the heavily depleted 2/14th and 2/16th Infantry Battalions – who had borne the brunt of the fighting around Isurava, Eora Creek and Templeton's Crossing – forming a composite unit of just two companies,[15][10] held a position astride the track which ran along the north–south spur line that protruded from the ridge's northern slopes.

[21] The 2/25th Infantry Battalion was subsequently laid down south of the ridge in depth, in the low ground forward of the Ua-Ule Creek, to provide a reserve force to be committed in case of emergency.

Meanwhile, the 25th Brigade's other two battalions – the 2/31st and 2/33rd – made preparations to launch an attack either side of the defensive line, to outflank the pursuing Japanese in an effort to cut the track at Nauro.

[7] The following day, 15 September, the other half of the III Battalion attempted to find the eastern flank of the Australian position, but found that the line was much longer than expected there also due to the earlier movement made by the 2/33rd during the preparatory phase of the battle.

Nevertheless, the Japanese found a gap in the Allied line in between the 3rd Infantry Battalion and the 2/33rd, seizing an opportunity to rush an Australian Militia section that had forgotten to post a sentry whilst expanding its pits.

Nevertheless, the Australian commander, Eather, decided to withdraw unaware of the dilemmas facing his opposite number, Kusunose, who had realised he was outnumbered with no reserves,[25] In reaching this decision, he potentially misjudged the tactical situation, perceiving that the Japanese attack could not be held any longer.

Having exhausted their supply line, which was increasingly being interdicted by US and Australian aircraft,[33] and as events elsewhere, particularly Guadalcanal, coupled with the earlier defeat around Milne Bay, turned in favour of the Allies, the Japanese were forced into adopting a more defensive posture in New Guinea.

Instead of a final stand, the fighting around Imita Ridge petered out into a series of small-scale patrol actions, before the Japanese began withdrawing north, beginning on 26 September.

[37] Pressing on to Efogi against little opposition, in late October the Australians reached Eora Creek and Templeton's Crossing,[38] which had earlier been the scene of heavy fighting during the Japanese advance.

A second battle was subsequently fought there as the Australians gained the vital ridge overlooking the creek at heavy cost against stiff opposition determined to buy time for the remainder of their comrades to make good their escape.