28 March – 6 April

The Battle of Slater’s Knoll (28 March – 6 April 1945) was a battle during the Second World War fought between Australian and Japanese forces on Bougainville Island.

Part of the Bougainville campaign, the battle occurred as a force of about 3,300 Japanese from the Japanese 6th Division supported by a sizeable concentration of artillery launched a counterattack against the main Australian offensive, concentrating their attacks on Slater’s Knoll near the Puriata River. The Australian troops belonged to the 7th Brigade, with the 25th Battalion being the most heavily engaged, although the 9th Battalion and the 61st Battalion also took part in the fighting.

Against Japanese tactics that included massed attacks, the Australians utilised armour and artillery, and in the end these proved telling. The final attack on the knoll came on the night of 4/5 April when 129 men from ‘B’ Company, 25th Battalion beat off an attack by a force of about 1,100 Japanese, killing 292. This proved to be the 7th Brigade’s final involvement in the campaign as they were relieved by the 15th Brigade shortly afterwards.

Overall, 620 Japanese were killed in the battle with another 1,000 estimated to have been wounded, while the Australians suffered 189 casualties.

Bougainville_Matilda_(AWM_018384)

Matilda tanks of the Australian 2/4th Armoured Regiment advancing towards Slater’s Knoll on 30 March 1945