The Allies of World War II conducted an air attack upon a cruiser force at the major Japanese base of Rabaul in November 1943. In response to the Allied invasion of Bougainville, the Japanese had brought a strong cruiser force down from Truk, their major naval base in the Caroline Islands about 800 miles north of Rabaul, to Rabaul in preparation for a night engagement against the Allied supply and support shipping. Allied carrier- and land-based planes attacked the Japanese ships, airfields, and port facilities on the island of New Britain to protect the Allied amphibious invasion of Bougainville. As a result of the Rabaul raids, the Japanese naval forces could no longer threaten the landings.