Bougainville Campaign
The Battle of Tsimba Ridge was an engagement of the Second World War involving Australian and Japanese forces. Part of the wider Bougainville Campaign of the Pacific theatre, the battle occurred in the northern sector of Bougainville Island between 17 January and 9 February 1945, when the lead battalion of the Australian 11th Brigade—the 31st/51st Infantry Battalion—advanced towards the Genga River as part of a drive north to the Bonis Peninsula.