Battle of Guadalcanal (1942–1943): The Allies Go on the Offensive

The Battle of Guadalcanal, or Guadalcanal campaign, was fought from 7 August 1942 to 9 February 1943 in the Solomon Islands. It was the first major Allied land offensive against Japan in the Second World War, launched to capture an airfield the Japanese were building on Guadalcanal. Six months of fighting on land, at sea and in the air ended with a Japanese withdrawal and marked the moment when the initiative in the Pacific passed to the Allies.

Background

After the Japanese defeat at the Battle of Midway in June 1942, American commanders looked for an opportunity to go on the offensive. In May Japan had occupied Tulagi, a small island with a good anchorage, and in July it began building an airfield on the north coast of nearby Guadalcanal. From there, Japanese bombers could threaten New Caledonia, Fiji and Samoa and the sea lanes between the United States and Australia, which the Battle of the Coral Sea had already shown to be contested.

The Allied plan, codenamed Operation Watchtower, was prepared in a hurry. Vice Admiral Robert Ghormley commanded the South Pacific Area, Vice Admiral Frank Jack Fletcher led the carrier force, and Rear Admiral Richmond Kelly Turner commanded the amphibious ships. The landing force was the 1st Marine Division under Major General Alexander Vandegrift.

Landing and the loss at Savo Island

On 7 August 1942 around 11,000 Marines landed on Guadalcanal and met little resistance; the Japanese construction workers and guards fled into the jungle, and the airfield was taken the next day. On Tulagi and the neighbouring islets of Gavutu and Tanambogo, about 3,000 Marines met fierce resistance from Japanese naval troops, who fought almost to the last man.

In the early hours of 9 August a Japanese cruiser force under Vice Admiral Gunichi Mikawa surprised the Allied warships guarding the transports near Savo Island. In little more than half an hour it sank the American heavy cruisers Quincy, Vincennes and Astoria and the Australian cruiser HMAS Canberra, killing over 1,000 Allied sailors. The Battle of Savo Island was one of the worst defeats in US Navy history. With Fletcher’s carriers already withdrawing, Turner took his transports away, leaving the Marines short of supplies and heavy equipment.

Holding Henderson Field

The Marines completed the airfield and named it Henderson Field after Major Lofton Henderson, a Marine pilot killed at Midway. The first aircraft arrived on 20 August. The mixed force of Marine, Navy and Army aircraft based there, known by the island’s codename as the Cactus Air Force, controlled the waters around the island by day.

Japan, at first underestimating the size of the American force, sent troops in small groups. On 21 August an attack by a detachment under Colonel Kiyonao Ichiki was destroyed at the Ilu River, often called the Battle of the Tenaru. On 12–14 September a larger force under Major General Kiyotake Kawaguchi attacked a ridge south of the airfield and was beaten off in what became known as Edson’s Ridge or Bloody Ridge. In late October the Japanese 17th Army under Lieutenant General Harukichi Hyakutake made its biggest attempt, with the 2nd Division under Lieutenant General Masao Maruyama; the assaults of 23–26 October failed with heavy losses.

By night, Japanese destroyers ran troops and supplies down the channel known as “the Slot”, a service the Allies called the Tokyo Express. On the night of 13–14 October the battleships Kongō and Haruna bombarded Henderson Field, destroying many aircraft, but the field kept operating.

The naval battles

The struggle for supply and air cover produced a series of naval battles. These included the Battle of the Eastern Solomons on 24–25 August, in which the Japanese light carrier Ryūjō was sunk; the night Battle of Cape Esperance on 11–12 October; and the Battle of the Santa Cruz Islands on 26 October, in which the American carrier Hornet was sunk. The carrier Wasp had already been sunk by a Japanese submarine on 15 September.

On 18 October Vice Admiral William F. Halsey replaced Ghormley, bringing new energy to the campaign. The decisive clash was the Naval Battle of Guadalcanal on 12–15 November 1942. In close-range night actions both American rear admirals, Daniel Callaghan and Norman Scott, were killed, and the light cruiser Juneau was sunk with the loss of nearly all its crew, including the five Sullivan brothers. But the Japanese battleships Hiei and Kirishima were sunk, and most of a large troop convoy was destroyed. Japan never again tried to land a major force on the island. So many ships went down between Guadalcanal, Savo and Florida Islands that the area became known as Ironbottom Sound.

Japanese withdrawal

In December 1942 the exhausted 1st Marine Division was relieved, and the US Army’s XIV Corps under Major General Alexander Patch took command. Japanese troops on the island, cut off from regular supply, were starving and weakened by malaria and dysentery; they called Guadalcanal “Starvation Island”. On 31 December the Japanese high command decided to abandon it.

In Operation Ke, carried out by destroyers on three nights in early February 1943, the Japanese navy evacuated about 10,600 soldiers so skilfully that the Americans did not realise until it was over. On 9 February 1943 Patch announced that organised resistance had ended.

By the numbers

Figures follow Richard B. Frank and other standard accounts; exact totals vary between sources.

Key people

• Alexander Vandegrift (1887–1973): commanded the 1st Marine Division and received the Medal of Honor.
• William F. Halsey (1882–1959): took over the South Pacific command in October 1942.
• Alexander Patch (1889–1945): led the final Army offensive that cleared the island.
• Harukichi Hyakutake (1888–1947): commanded the Japanese 17th Army.
• Isoroku Yamamoto (1884–1943): Japanese naval commander, who was killed in April 1943 when his aircraft was shot down on a flight to inspect positions in the Solomons, an event covered in the death of Admiral Yamamoto.

Solomon Islanders also played a vital role as scouts, guides and labourers, and Australian and British coastwatchers such as Martin Clemens radioed warnings of Japanese air raids.

Timeline

• 1942, July: Japan begins building an airfield on Guadalcanal.
• 1942, 7 August: US Marines land on Guadalcanal and Tulagi.
• 1942, 9 August: Four Allied cruisers are sunk at the Battle of Savo Island.
• 1942, 21 August: The Ichiki detachment is destroyed at the Ilu River.
• 1942, 12–14 September: The Battle of Edson’s Ridge.
• 1942, 23–26 October: The main Japanese assault on Henderson Field fails.
• 1942, 12–15 November: The Naval Battle of Guadalcanal.
• 1942, 31 December: Japan decides to withdraw.
• 1943, 1–7 February: Operation Ke evacuates the surviving Japanese troops.
• 1943, 9 February: Organised resistance is declared over.

Why it matters

Guadalcanal was the turning point of the war in the South Pacific. Japan lost thousands of irreplaceable pilots, many warships and an army, while the Allies gained a base for the long advance through the Solomons and on to the central Pacific, including later battles such as Tarawa. It showed that Japanese forces could be defeated on land and set the pattern of hard-fought island campaigns that followed.