The 2/25th Battalion arrived in Adelaide, South Australia on 10 March 1942, having made the voyage from Egypt aboard the American troopship USS Mount Vernon.
Following this they undertook training at Woodside Camp before moving north to Caboolture, Queensland in May. Undertaking marksmanship training at the rifle range at Enoggera in Brisbane and specific jungle training in July, later in early August the battalion carried out amphibious landing training, undertaking practice assaults on Bribie Island, before carrying out further marksmanship and physical fitness training as they prepared for the order to proceed overseas as the situation in New Guinea became quite serious.
 This order finally came on 31 August, following a brigade-level demonstration exercise that was viewed by General Douglas MacArthur the previous day.

Embarking on the SS Van De Lijn and Katoomba on 1 September 1942, the battalion proceeded to Port Moresby, via Townsville.
The voyage was not without incident, as the Van De Lijn was involved in a collision with the troopship Perthshire, resulting in the death of one member of the 2/25th Battalion and injuries to five others.
Nevertheless, they arrived in Port Moresby on 9 September, after having put into Townsville for a couple of days before proceeding on to New Guinea.

They spent two days at a staging camp at Murray Barracks where they were issued the new jungle green uniforms before setting out on 11 September, along with the rest of the 25th Brigade, to carry out the march towards Ioribaiwa.
Arriving there on 15 September, they took part in the last Australian withdrawal of the campaign, falling back on Imita Ridge, before the Japanese themselves were forced to withdraw having exhausted their supply lines.
Following this, the battalion took part in the Australian advance towards Gona, subsequently taking part in significant battles at Templeton's Crossing and Gorari throughout October and November, before taking part in the Battle of Buna–Gona in late November–early December.

In December they move to a rest camp at Donadabu before finally, in January 1943, the battalion was withdrawn to Australia for rest and re-organisation.
They remained in Australia for the next six months training on the Atherton Tablelands.

They returned to New Guinea, however, arriving at Port Moresby on 22 July, aboard the troopship Duntroon in advance of the 25th Brigade's advance on Lae.
Billeted at the Six Mile Valley camp under canvas, they carried out a number of sub-unit level exercises which culminated in a brigade-level exercise in late August and early September before being flown to Nadzab on 7 September.
From there they took part in the Salamaua–Lae campaign, which saw the 7th Division to which the battalion was attached drive on Lae through the Markham Valley.
Advancing through the plantations that lined the Markham Road, they encountered only light resistance and the 2/25th, in the vanguard of the Australian force, was the first to enter the town on 16 September.

Later in September the battalion was flown to Kaipit, from where they carried out patrols in support of the Finisterre Range campaign, operating in an area that included the Markham and Ramu Valleys and the Finnisterre Range.
During this time the battalion was involved in a series of relatively minor contacts, with the most significant coming on 13 September around Whittaker's Bridge, near Heath's Plantation, and then on the night of 12/13 December around the Evapia River and at Kesawai.
It was during the fighting at Heath's Plantation on 13 September 1943 that Richard Kelliher, from 'B' Company performed the deeds that later led to him receiving the Victoria Cross.

In January 1944, the battalion handed over their area of responsibility to the 24th Battalion and was withdrawn back to Port Moresby.
From there, it embarked for Australia in February 1944.
The 2/25th Battalion arrived in Adelaide, South Australia on 10 March 1942, having made the voyage from Egypt aboard the American troopship USS Mount Vernon. Following this they undertook training at Woodside Camp before moving north to Caboolture, Queensland in May. Undertaking marksmanship training at the rifle range at Enoggera in Brisbane and specific jungle training in July, later in early August the battalion carried out amphibious landing training, undertaking practice assaults on Bribie Island, before carrying out further marksmanship and physical fitness training as they prepared for the order to proceed overseas as the situation in New Guinea became quite serious.  This order finally came on 31 August, following a brigade-level demonstration exercise that was viewed by General Douglas MacArthur the previous day.
Embarking on the SS Van De Lijn and Katoomba on 1 September 1942, the battalion proceeded to Port Moresby, via Townsville. The voyage was not without incident, as the Van De Lijn was involved in a collision with the troopship Perthshire, resulting in the death of one member of the 2/25th Battalion and injuries to five others. Nevertheless, they arrived in Port Moresby on 9 September, after having put into Townsville for a couple of days before proceeding on to New Guinea.
They spent two days at a staging camp at Murray Barracks where they were issued the new jungle green uniforms before setting out on 11 September, along with the rest of the 25th Brigade, to carry out the march towards Ioribaiwa. Arriving there on 15 September, they took part in the last Australian withdrawal of the campaign, falling back on Imita Ridge, before the Japanese themselves were forced to withdraw having exhausted their supply lines. Following this, the battalion took part in the Australian advance towards Gona, subsequently taking part in significant battles at Templeton's Crossing and Gorari throughout October and November, before taking part in the Battle of Buna–Gona in late November–early December.
In December they move to a rest camp at Donadabu before finally, in January 1943, the battalion was withdrawn to Australia for rest and re-organisation. They remained in Australia for the next six months training on the Atherton Tablelands.
They returned to New Guinea, however, arriving at Port Moresby on 22 July, aboard the troopship Duntroon in advance of the 25th Brigade's advance on Lae. Billeted at the Six Mile Valley camp under canvas, they carried out a number of sub-unit level exercises which culminated in a brigade-level exercise in late August and early September before being flown to Nadzab on 7 September. From there they took part in the Salamaua–Lae campaign, which saw the 7th Division to which the battalion was attached drive on Lae through the Markham Valley. Advancing through the plantations that lined the Markham Road, they encountered only light resistance and the 2/25th, in the vanguard of the Australian force, was the first to enter the town on 16 September.
Later in September the battalion was flown to Kaipit, from where they carried out patrols in support of the Finisterre Range campaign, operating in an area that included the Markham and Ramu Valleys and the Finnisterre Range. During this time the battalion was involved in a series of relatively minor contacts, with the most significant coming on 13 September around Whittaker's Bridge, near Heath's Plantation, and then on the night of 12/13 December around the Evapia River and at Kesawai. It was during the fighting at Heath's Plantation on 13 September 1943 that Richard Kelliher, from 'B' Company performed the deeds that later led to him receiving the Victoria Cross.
In January 1944, the battalion handed over their area of responsibility to the 24th Battalion and was withdrawn back to Port Moresby. From there, it embarked for Australia in February 1944.
2/25th Battalion (Australia)