The Battle of the Bismarck Sea was a military engagement that took place between March 2 and March 4, 1943, in the southwest Pacific Theater during World War II. It was a pivotal confrontation between Allied forces, primarily composed of American and Australian military units, and the Imperial Japanese Navy. The battle was centered around an attempted Japanese convoy sailing from Rabaul to reinforce their troops in New Guinea, where Allied operations aimed to keep the Japanese forces from strengthening their positions.

The Allied forces gained intelligence about the Japanese movements and planned an ambush. Utilizing land-based aircraft from bases in the Solomon Islands, they engaged the Japanese fleet, effectively targeting the transport ships. The result was an overwhelming defeat for Japan, with significant losses including over 60 aircraft and several transport vessels, which were either sunk or damaged beyond repair. This strategic victory significantly impeded Japan's capacity to sustain its military personnel in the Pacific theater, particularly in New Guinea.

The battle demonstrated the effectiveness of air power in naval warfare and the importance of intelligence and coordinated strikes in achieving military objectives. General Douglas MacArthur, the commander of Allied forces in the Southwest Pacific, praised the operation as a successful execution of strategy, solidifying air superiority and disrupting the enemy's supply lines, which contributed greatly to the overall strategy of the Allies in the region.