Part of the Salamaua–Lae campaign, the battle involved Australian and Japanese troops who clashed on the ridge, which was about 20 kilometres (12 mi) south of Salamaua, near Mubo, over the course of several days.

The fighting around Lababia Ridge took place at the same time as the Battle of Mubo, after two battalions of Japanese infantry launched a counter-attack on a depleted Australian company.

In March 1943, Australian troops from the 2/7th Infantry Battalion had pushed forward from Wau, which had been secured in late January and set up a defensive position on Lababia Ridge[1] a 3,000-foot (910 m) feature about 20 kilometres (12 mi) south of Salamaua, near Mubo, which was situated around the Bitoi and Buyawim Rivers that was, according to historian John Miller, strategically important as it provided clear observation of "Nassau Bay to the southeast, Bitoi Ridge to the north, and the Komiatum Track which served as the line of communications from Salamaua to the Japanese facing the Australians".

[7] They had been dispatched earlier in May to support the 2/7th's right flank, and had carried out several reconnaissance patrols towards Duali and the coast, to gather information prior to the landing of US troops around Nassau Bay.

In late May, the Japanese high command determined that they would attempt to force the Australians off Lababia Ridge, and began making preparations for an assault, rotating their forces in the area, with the exhausted 102nd Infantry Regiment, which had been fighting the Australians since the Battle of Wau, being replaced by two battalions of the 66th Infantry Regiment, under the command of Colonel Katsutoshi Araki.

The following day, 21 June, Australian patrols noticed signs of Japanese activity along the track towards the observation post that had been established further east along the ridge.

Meanwhile, amidst heavy rain, the Japanese recovered their wounded and continued to reduce the booby traps in front of the Australian positions.

The fighting continued early the following day, with the Japanese laying down heavy machine gun and mortar fire, but this was only designed to help cover their withdrawal.

[6][11] Left mainly to his own devices during the battle, for his leadership during the main Japanese assault on the Australian positions around Lababia Ridge, Dexter was later awarded the Distinguished Service Order, while several of the Australian platoon commanders – Lieutenants Edward Exton and Laurence Roach – received Military Crosses, and one of the platoon sergeants, Sergeant John Hedderman, received a Military Medal.