The Battle of the Coral Sea, fought during 4–8 May 1942, was a major naval battle in the Pacific Theater of World War II between the Imperial Japanese Navy and Allied naval and air forces from the United States and Australia. The battle was the first action in which aircraft carriers engaged each other, as well as the first in which neither side's ships sighted or fired directly upon the other.
In an attempt to strengthen their defensive positioning for their empire in the South Pacific, Imperial Japanese forces decided to invade and occupy Port Moresby in New Guinea and Tulagi in the southeastern Solomon Islands. The plan to accomplish this, called Operation MO, involved several major units of Japan's Combined Fleet, including two fleet carriers and a light carrier to provide air cover for the invasion fleets, under the overall command of Shigeyoshi Inoue. The U.S. learned of the Japanese plan through signals intelligence and sent two United States Navy carrier task forces and a joint Australian-American cruiser force, under the overall command of American Admiral Frank J. Fletcher, to oppose the Japanese offensive.
