The Guadalcanal Campaign was fought between August 7, 1942, and February 9, 1943, in the Pacific theatre of World War II. This campaign, which was a decisive and strategically important campaign of World War II, was fought on the ground, at sea, and in the air between Allied forces against Imperial Japanese forces. The fighting took place on and around the island of Guadalcanal in the southern Solomon Islands, and was the first major offensive launched by Allied forces against the Empire of Japan.
On August 7, 1942, Allied forces, mainly from the United States, started landings on the islands of Guadalcanal, Tulagi, and Florida in the southern Solomons with the aim to make supply routes between the U.S., Australia, and New Zealand safer. The Battle of Guadalcanal was one of the first long campaigns in the Pacific.
Background
Strategic considerations
On 7 December 1941, Japanese forces attacked the neutral United States Pacific Fleet at Pearl Harbor, Hawaii. The attack killed almost 2,500 people and damaged much of the US battleship fleet, starting a war between the two nations next day. The initial goals of Japanese leaders were to destroy the US Navy, seize lands rich in natural resources, and establish strategic military bases to defend Japan's empire in the Pacific Ocean and Asia. To do this, Japanese forces captured the Philippines, Thailand, Malaya, Singapore, Burma, the Dutch East Indies, and many small islands. Joining the U.S. in the war against Japan were the rest of the Allied powers, several of whom, including the United Kingdom, Australia and the Netherlands had also been attacked by Japan.
The naval battle of the Coral Sea prevented a quick Japanese conquest of Australia and the Battle of Midway reduced Japan's carrier forces.
The Allies chose the southern Solomon Islands including Guadalcanal, as the first target. The Imperial Japanese Navy (IJN) had occupied Tulagi in May 1942 and had constructed a seaplane base nearby. Allied concern grew when, in early July 1942, the IJN began constructing a large airfield at Lunga Point on Guadalcanal. From there, Japanese long range bombers would threaten the East Coast of Australia. By August 1942, the Japanese had about 900 naval troops on Tulagi and nearby islands and 2,800 people on Guadalcanal. These bases would protect Japan's major base at Rabaul, threaten Allied supply and communication lines and establish base for attacks against Fiji, New Caledonia and Samoa.
The Japanese planned to send 45 fighters and 60 bombers to Guadalcanal. In 1942 these aircraft could provide air cover for Japanese naval forces advancing into the South Pacific.
The Allied plan to invade the southern Solomons was thought of by U.S. Admiral Ernest King, Commander in Chief, United States Fleet. He wanted to take the islands away from the Japanese. With Roosevelt's agreement, King also wanted to invade Guadalcanal. Because the United States supported Great Britain's idea of defeating Germany before Japan, the Pacific war had to compete for troops and resources with the European war.
Therefore US Army General George C. Marshall was against King's proposed attacks and asked who would command the operation. King replied that the Navy and Marines would do it themselves and instructed Admiral Chester Nimitz to plan the attacks. King won the argument with Marshall and the invasion went ahead.
The Guadalcanal attack would be carried out in at the same time as an Allied offensive in New Guinea under Douglas MacArthur. The goal was to capture the Admiralty Islands and the Bismarck Archipelago, including the major Japanese base at Rabaul. Eventually they would take the Philippines. The U.S. Joint Chiefs of Staff put Vice Admiral Robert L. Ghormley in command on 19 June 1942, to direct the attack in the Solomons.
Admiral Chester Nimitz, based at Pearl Harbor, was the overall Allied commander in chief for Pacific forces.
Task force
In preparation for the attack in the Pacific in May 1942, the U.S. 1st Marine Division moved from the United States to New Zealand. Other Allied land, naval and air force units were sent to other Pacific islands. The attack was codenamed Operation Watchtower, with the date set for 7 August 1942.
At first, the attacks were planned just for Tulagi and the Santa Cruz Islands, and not Guadalcanal. When the Allies discovered the Japanese airfield on Guadalcanal, its capture was added to the plan and the Santa Cruz operation was dropped. The Japanese knew Allied forces were moving but thought they were going to Australia and perhaps Port Moresby in New Guinea.