The stand at Isurava
26-31 August 1942
In late August both the Australians and the Japanese were greatly reinforced and prepared for a decisive battle at Isurava. While the Japanese were victorious they failed to achieve their main objective - the total destruction of Maroubra Force...
Animated map of the stand at Isurava
Plans and forces present
Since the loss of Kokoda airstrip the Australian objective had been to drive back the Japanese and recover it. This would ensure a regular supply of food and ammunition. However by the last week of August it was realised that the Japanese were now too strong so Brigadier Potts' orders were changed. He was told to adopt a defensive stance and prevent the Japanese penetrating the Owen Stanley Range towards Port Moresby.
Maroubra Force, under Potts' command, dug in and awaited the Japanese attack on both sides of Eora Creek at Isurava. Along the bottom of a steep V-shaped gorge the creek ran north towards Kokoda. On the left, as the Australians looked at it, was Isurava village where the 2/14th and 39th Battalions stood. On the right side of the gorge was 53rd Battalion and a half of 2/16th Battalion. The other half of this battalion was held in reserve. With the various headquarters and detachments of 2/6th Field Ambulance, Australia New Guinea Administrative Unit, the Royal Papuan Constabulary and the Papuan Infantry Battalion, there were about 2290 men present.
Horii, the Japanese commander, was anxious to destroy the Australian force as soon as possible, before it either counterattacked towards Kokoda or withdrew further into the mountains. Consequently, when the main body of the Nankai Shitai arrived by sea, he ordered it immediately to force march 120 kilometres to Isurava. Japanese supply difficulties had resulted in the overloading of their men with food and ammunition. The combination of a week long forced march and heavy packs resulted in many Japanese soldiers falling out along the way to Isurava. These men failed to arrive in time for the battle leaving Horii with about 3000 men with which to attack.
Horii planned the total destruction of the Australians by a double envelopment. He had four infantry battalions but wished to keep one out of the battle so it would be fresh for the pursuit of the enemy afterwards. The others, the three battalions of 144 Regiment were to be deployed thus: 1/144 would attack and pin the Australian centre about Isurava. The second battalion, 2/144, would attack along the eastern side of the gorge against the Australian right flank. If the Australians did not commit their reserve to halt this battalion, it would proceed to cut the track junction in the Australian rear at Alola. The final Japanese move would be to send the third of the infantry battalions, 3/144, around the Australian left. If all went as planned there would be no Australian reserves left to oppose this move which would complete the encirclement of the defenders.
The battle of Isurava
Horii's plan came completely unstuck. First 1/144, the battalion which was to make the frontal attack, was in poor condition. It had been in Papua longest of all his battalions and had taken the most casualties. When Horii's main attack began on 27 August, 1/144 did not go at the Australians with the vigour Horii expected so he strengthened 1/144 with one company from 3/144 thus weakening 3/144 for its later move around the Australian left. Though reinforced, 1/144 continued to disappoint Horii. On 29 August an Australian counterattack, in which Private Bruce Kingsbury won a Victoria Cross, cut right through a company of this battalion and killed the company commander.
The second problem for the Japanese was that most of their artillery had not been able to keep up with the forced march. Just three of ten artillery pieces were available. The battalion gun of 2/144 went with it across to the east of the gorge. The other two guns were placed on high ground overlooking Isurava. From there they could fire in support of any of the Japanese attacks.
On 27 August to the east of the Eora Creek gorge, 2/144 failed to make much headway against the Australian 53rd and 2/16th Battalions. The next day the Japanese battalion commander decided to make a flank march through the jungle to get behind the Australians. His battalion became lost in the jungle and as a result there was little fighting east of the gorge this day.
On the west side of the gorge when 3/144 made its flank march around the Australian left it too became lost. It blundered into the left of the Australian line instead of getting into the Australian rear as intended. Having made little progress so far Horii felt obliged to commit the battalion he had intended to keep fresh for the pursuit. This battalion was sent on a wide outflanking move well around the Australian left and was to emerge on the track far in their rear about Alola village. It too found it impossible to navigate accurately in the jungle. It wandered far from the battle and did not emerge until the fighting was over. 'At Isurava', this battalion commander said, 'we didn't fire a shot or lose a man.'
Japanese blunders notwithstanding, by the night of 29 August the Australians had committed all their reserves and Lt Col Key of 2/14th Battalion advised Potts that the position could not be held on the following day. Potts accepted this advice and withdrew Maroubra Force to Isurava rest house, one kilometre south of the original position. Meanwhile to the east of the gorge no Australian withdrawal was necessary. There on 29 August the attack of 2/144 was again held up by 53rd and 2/16th Battalions.
At dawn on 30 August the Japanese 1/144 Battalion, unaware of the Australian withdrawal on the Isurava side of the gorge, bombarded and assaulted the now empty Australian position. A kilometre south of there, as the Australians settled into the Isurava rest house position, they came under attack from the high ground to their west. What had happened was 3/144, which had the previous day wandered unintentionally into the Australian left, swung out west then south again that night and made for what they supposed would be the Australian rear. Instead they found the Australians in their new position at Isurava rest house. By now more Japanese guns had arrived and a total of eight were available to bombard the new Australian position in support of the attack of 3/144. This bombardment contributed to Potts' decision that the short retreat to Isurava rest house was not the answer to his problem. Only a complete withdrawal of Maroubra Force would prevent its destruction.
The Australian retreat
Breaking contact with an aggressive enemy is a most difficult operation of war and at Isurava it was only partially successful. Japanese attacks during the retreat caused the dispersion of hundreds of Australians into the jungle. Over the next week most of these men were able to make their way back to the main body moving south along the Kokoda track. One notable exception was Colonel Keys, commander of 2/14th Battalion. He was captured, taken back to the Japanese base, interrogated then executed.
While Isurava was a notable Japanese victory Horii had failed in his main aim, to completely destroy the Australian force. Nor did the casualties inflicted by either side favour the Japanese. Over the period from 25 August to 31 August the Australians lost 99 killed and 111 wounded. The Japanese lost 140 killed and 231 wounded.