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The Battle of Guadalcanal

U.S. Marines invade the small island of Guadalcanal (7 August 1942).

U.S. Marines invade the small island of Guadalcanal (7 August 1942).

The Guadalcanal Campaign Explained

  • Name of Event: Guadalcanal Campaign
  • Start of Event: 7 August 1942
  • End of Event: 9 February 1943 (Six Months and Two Days)
  • Location: Guadalcanal, British Solomon Islands
  • Participants: United States and Japanese Empire
  • Outcome: Allied Victory

The Battle for Guadalcanal (codenamed Operation Watchtower) began on 7 August 1942 and served as the first major operation against the Japanese Empire in World War Two. Supported by American, Australian, and New Zealand warships, U.S. Marines landed on Guadalcanal facing fierce resistance from the Japanese defenders. Allied forces hoped that control of Guadalcanal and its surrounding islands would provide a support base for future operations in the region.

Victory, in the end, proved very costly for both sides. However, the American victory also served as a transition for Allied forces and their campaign against the Japanese Empire as it signaled a turning point from defensive to offensive military operations in the war, and helped lead to additional victories in the Solomon Islands, Central Pacific, and New Guinea.

Marines at Guadalcanal.

Marines at Guadalcanal.

Guadalcanal's Strategic Importance in World War II

Japanese forces first took control of Guadalcanal on 6 July 1942 with a force of approximately 2,000 men. Due to the island’s strategic location, the Japanese immediately began construction on a large airfield that could support air-based operations around the Solomon Islands. Covered with dense jungle (and approximately 2,047 square miles in size), the island offered a perfect defense point for its Japanese defenders once American forces arrived in August (only a month later).

For the Americans, Guadalcanal offered similar strategic importance. Situated within the Solomon Islands, the capture of Guadalcanal was crucial as it would serve as a major base of operations for the U.S. Navy and Marines against Japanese forces. More importantly, the disruption of Japanese activities on Guadalcanal would help to eliminate Japanese air superiority in the region, given that a large airbase was already well underway by the time Marines landed in August of 1942. Eliminating this future airbase would, in turn, help to protect vital supply lines for the American Navy in their support of Australia, and allow for naval operations in the sector to be conducted with little interference.

Marines making an amphibious assault.

Marines making an amphibious assault.

Invasion of Guadalcanal

In a rapid attack that took the Japanese by surprise, the United States funneled approximately 6,000 Marines onto the island through a massive amphibious assault on 7 August 1942. What was expected to be a quick victory, however, soon turned into a bitter struggle as the Japanese began to land reinforcements on the island through both the air and by sea. For approximately six months, fierce fighting continued between the Marines and Japanese who refused to surrender to American forces. By October of 1942, Japanese forces on Guadalcanal reached a peak of 36,000 troops. American forces, in contrast, reached a peak strength of 44,000 troops by January of 1943.

In their initial landing on the island, American forces were able to arrive unnoticed by the Japanese due to bad weather covering their advance. In their “midnight assault” of the island, U.S. Marine forces split into two separate groups, with the first group assaulting the Tulagi and Florida islands, and group two making the main assault on Guadalcanal itself. Covered by heavy naval bombardment and extensive air support from carrier aircraft, the Marines slowly advanced on the islands, facing fierce resistance from the Japanese who fought to the last man (despite being vastly outnumbered). By 9 August, Tulagi, Gavutu, and Tanambogo islands were secured at the expense of 122 American lives.

In the initial stages of the assault on Guadalcanal’s main island, the Marines encountered little resistance from the surprised Japanese defenders; allowing for an additional 11,000 Marines to land on the island with relative ease. By 8 August, the Japanese airfield had already been captured by American forces with minimal casualties. Japanese aircraft from the Solomon Islands, however, continued to fight ferociously against the U.S. Navy awaiting offshore, and managed to down 19 American aircraft, and destroy the transport USS George F. Elliot (before losing thirty-six aircraft of their own during the attacks). The American destroyer, USS Jarvis was also heavily damaged in the air attacks. Concerned about their aircraft losses, the American carrier group withdrew from the area on the evening of 8 August, leaving the Marines ashore with no carrier-based aircover, and less than half of the needed supplies for the campaign.

Henderson Field.

Henderson Field.

Establishment of "Henderson Field"

With little air support, the eleven-thousand Marines on Guadalcanal formed a defensive perimeter around both Lunga Point at the captured Japanese airfield. Using captured Japanese equipment, the Marines began construction on the airfield immediately to prepare it for incoming American transport planes and began to systematically shuttle their dwindling supplies within their newly established perimeter line.

On 12 August, the captured airfield was renamed “Henderson Field” after Marine aviator, “Lofton R. Henderson” who was killed at the Battle of Midway. Only six days later, the airfield was fully operational and ready to receive planes. By 20 August, two squadrons of Marine aircraft were delivered to Henderson Field and were quickly put to use against the daily bombing raids conducted by the Japanese. In the meanwhile, Japanese forces continued to regroup outside the Marines' perimeter as hundreds of Japanese troops were landed by sea and air to reinforce their own defensive positions.

During the early morning hours of 21 August, Japanese forces from the 17th Army conducted a frontal assault against the Marines along a position known as “Alligator Creek.” The Marines were able to overwhelm the Japanese, however, killing nearly 800 soldiers. As the battle at Alligator Creek subsided, the Japanese dispatched a massive fleet of ships from their naval base at Truk to resupply and reinforce their garrison at Guadalcanal. The fleet consisted of three carriers and approximately thirty additional warships. Admiral Fletcher of the United States Navy planned to counter the Japanese offensive with the implementation of three carrier battle groups around Guadalcanal. After two days of naval warfare between the two fleets, both sides were forced to retreat from the area after suffering extensive damage.

Lunga Perimeter.

Lunga Perimeter.

The Lunga Perimeter

By the end of August, nearly 64 American aircraft had arrived at Henderson Field along with U.S. Marine Brigadier General, Roy S. Geiger, who took command of air operations at Henderson Field. Air battles over Guadalcanal became a daily routine for the following months as American and Japanese fighter-aircraft engaged in countless dogfights and bombing runs over the island. Marine pilots maintained a strategic advantage at Guadalcanal, however, due to the fact that approaching Japanese aircraft were forced to fly nearly four hours from their base in Rabaul; giving American pilots ample time to prepare for attacks and to engage enemy fighters before they even reached the island.

Edson's Raiders

As fighting in the air continued unabated, General Alexander Vandegrift (on the ground) began to intensify efforts to strengthen the Marines' defensive perimeter. Three Marine battalions which included the elite 1st Raider Battalion (Edson’s Raiders), the 1st Parachute Battalion, and the 1st Battalion, 5th Marine Regiment were brought in to reinforce the Lunga perimeter in preparation for massive Japanese attacks. The addition of these three battalions brought the total number of Marine forces to 12,500 men on Guadalcanal.

Japanese POWs.

Japanese POWs.

The Tokyo Express

As the Marines intensified their efforts to develop a stable defensive perimeter, the Japanese increased their efforts to deploy additional troops on Guadalcanal through a system that became known as the “Tokyo Express.” Through their naval base in the Shortland Islands, Japanese destroyers made nightly round-trips through a narrow route known as “The Slot.” Night-time deliveries of troops and supplies minimized contact with Allied aircraft and American ships and provided much-needed medical and food supplies to the growing number of Japanese troops on Guadalcanal. The use of destroyers in delivering troops and supplies also had a downside, however, as heavy equipment (such as artillery and vehicles) was greatly hampered since the ships were not designed for this sort of shipment. Slow-moving transport ships were inefficient for this purpose as they could not make the trek to Guadalcanal during a single night; thus, exposing the unarmed boats to American aircraft.

For whatever reason, Japanese forces continued to maintain control of the sea during the night hours for much of the Guadalcanal campaign; a curious situation that only added to the duration of the military operation. For this reason, Japanese forces were able to land an additional 5,000 troops on Guadalcanal by the end of September (along Taivu Point).

Marine Raiders Patch.

Marine Raiders Patch.

The Battle of Edson's Ridge

As both sides settled in along the Lunga perimeter, fighting intensified on the night of 12 September 1942 with General Kawaguchi’s attack near Henderson Field. After splitting his forces into three separate divisions, Kawaguchi planned to make a surprise night attack on the Lunga perimeter with approximately 3,000 men, leaving 250 Japanese soldiers to defend their supply point at Taivu base.

Raid on Taivu

As the Japanese troops deployed for their attack (on 7 September), however, Lieutenant Colonel Merrit Edson (commander of the elite Edson’s Raiders) staged a pre-emptive attack on Taivu after learning from native scouts of Japanese troop movements away from Taivu. Edson planned to use the large-scale Japanese deployment to his advantage by using his Marine Raiders to wipe out the remaining Japanese forces that were left to defend Taivu and, in turn, destroy their supplies and equipment. Using boats to insert his men near Taivu, Edson’s men managed to capture the nearby village of Tasimboko on the night of 8 September and forced the remaining Japanese to retreat into the jungles of Guadalcanal after a brief firefight. During their retreat, Edson and his men discovered vast quantities of medical supplies, ammunition, and a powerful radio station that was being used to direct Japanese reinforcements to the island. After destroying most of the equipment and supplies, Edson and his Raiders returned to the Lunga perimeter with captured documents and enemy intelligence that detailed Kawaguchi’s battle plans for the upcoming night attack.

Although Edson and the other Marine officers were unable to determine the precise areas that the Japanese planned to attack, they believed that the most probable zone of entry would be along the Lunga River, just south of Henderson Field. At nearly a thousand yards long, the narrow coral ridge offered a natural avenue of attack since it was relatively undefended against enemy attacks. To counter this, Edson and 840 of his Raiders (11 September) positioned themselves along the ridge in preparation for the expected attack.

Japanese Assault

The attack occurred on the night of 12 September 1942, as Kawaguchi’s First Battalion attacked Edson’s Raiders in their assault on the ridge. Once it became clear that the ridge could not be taken easily, Kawaguchi funneled all of his 3,000 troops (along with artillery) into the narrow ridge in a desperate attempt to push Edson’s Raiders out of their zone of attack. The Raiders (outnumbered nearly four to one) fought courageously, holding off wave-after-wave of enemy attacks. Although the Japanese managed to break Edson’s lines at one point, Marine defenders guarding the northern sector of the ridge rapidly halted Kawaguchi’s men with a ferocious counterattack.

As the Japanese fell back to regroup, Edson’s Raiders fell back to the center of the ridge (a point known as Hill 123). Throughout the remainder of the night, the Raiders defeated wave-after-wave of Japanese assaults. By the end of the night, Kawaguchi was forced to retreat towards the Mantanikau Valley after losing over 850 men to the Marine defenders (compared to 104 Marines). Colonel Edson was later awarded the Medal of Honor for his actions along the ridge (which became affectionately known as “Edson’s Ridge”).

Colonel Edson (second from right, bottom row).

Colonel Edson (second from right, bottom row).

Additional Reinforcements

As news of Kawaguchi’s defeat reached Tokyo on 15 September 1942, General Hyakutake along with other top members of the Japanese Army and Navy concluded unanimously that Guadalcanal was developing into a decisive battle of the war. In response, Hyakutake redirected forces from his New Guinea campaign (a major Japanese offensive that was close to achieving victory) to Guadalcanal. By October, an additional 17,500 Japanese troops were delivered to the island in preparation for a major offensive scheduled to begin on 20 October 1942.

As it became clear to the American forces that the conflict at Guadalcanal was only strengthening with each passing day, American commanders further intensified their efforts to shore up their defenses of the Lunga Perimeter. On 18 September, an additional 4,157 Marines from the Third Provisional Marine Brigade, 137 vehicles, and tremendous amounts of fuel and ammunition were delivered to Guadalcanal. Although the battle for the island reached a lull for several weeks (due to poor weather conditions), naval attacks continued offshore as Japanese submarines managed to strike several American warships. In a surprise attack, the Japanese even managed to sink the U.S. Aircraft Carrier Wasp, leaving only the carrier Hornet to provide direct support to the South Pacific.

Reinforcements to both the Japanese and American air power was intensified during the lull in combat as well, with approximately 85 Japanese aircraft delivered to Rabaul Island and nearly 23 Marine aircraft delivered to Henderson Field.

Jungle conditions at Guadalcanal.

Jungle conditions at Guadalcanal.

Mantanikau and the Battle for Henderson Field

Following their defeat against Edson and his Marine Raiders, small skirmishes continued until the middle of October between Japanese forces and Marines around the area of Mantanikau. Japanese battleships, such as the Kongo and Haruna, also remained within the area and provided naval support to the Japanese troops on Guadalcanal through a bombardment of Henderson Field. Although the bombardment managed to destroy numerous American aircraft, the airfield remained intact during the duration of the attacks, allowing Marine pilots to counterattack; albeit with limited success.

Second Attack on Henderson Field

As these skirmishes and exchanges continued, the Japanese were provided ample time to regroup for a second attack against Henderson Field on 23 October 1942. During their assault on Henderson Field, the Japanese faced stiff American resistance as newly installed Browning machine guns and reserve units from the U.S. Army’s 164th Infantry Regiment had been brought in to reinforce the Marine perimeter only days prior to the attack. By 25 October, the Japanese had lost 553 KIA (killed in action), along with an additional 479 troops that were critically wounded in the Japanese 29th Regiment alone. For the Japanese 164th Regiment, over 975 troops were killed. In total, Marine forces estimated Japanese casualties to be around 2,200 men for the duration of their assault on Henderson Field.

Naval battle near Guadalcanal.

Naval battle near Guadalcanal.

Battle of the Santa Cruz Islands

While Kawaguchi’s offensive against Henderson Field was underway, Japanese warships moved into positions along the southern sector of the Solomon Islands in an attempt to engage with American and Allied ships operating in the area. On 26 October 1942, the two fleets engaged just north of the Santa Cruz Islands. In the exchange of naval gunfire and aerial attacks, the U.S. Carrier Hornet was sunk in the battle, whereas the USS Enterprise faced tremendous damage, forcing the Americans to retreat. Japanese forces, however, met a similar fate, as two of their carriers were heavily damaged in the battle. In addition, Japanese forces suffered tremendous losses to both aircraft and personnel.

Quote by Japanese Officer

"Most of the men are stricken with dysentery... starvation is taking too many lives and it is weakening our already extended lines. we are doomed."

— Major General Kensaku Oda

By November, American forces initiated both a naval and land-based offensive to end the stalemate with the Japanese on Guadalcanal. As Marine forces began to break out of their perimeter defense in pursuit of Japanese forces, the Allied Navy was able to score major victories against the Japanese and their efforts to reinforce Guadalcanal. In the early days of November, the U.S. Navy managed to sink half of the transport ships being used to funnel the Japanese 38th Infantry Division to the island; reducing the Japanese division down to the size and strength of a regiment on Guadalcanal. With reinforcements and supplies cut off, Marine forces expanded their offensive into the Mantanikau River and cleared the area of enemy troops by the end of the month.

Final Marine Offensive

In December, American troops conducted a final push against the Japanese defenders on Guadalcanal with the implementation of the U.S. XIV Corps. After withdrawing the First Marine Division from the battle for a well-deserved recuperation, the Second Marine Division along with the U.S. Army’s 25th Infantry Division and the Americal Division were brought in to continue the attack on dwindling Japanese forces. Facing starvation and a lack of supplies, the Japanese were placed in a dire situation by the beginning of January 1943, as American victory was only inevitable.

On 10 January 1943, the U.S. XIV Corps began their final push against the Japanese defenders, forcing the remaining fighters (by 8 February) to be evacuated via Cape Esperance. By 9 February 1943, Guadalcanal was officially designated “secure” by American forces, after approximately six months of continuous combat.

Concluding Thoughts

In closing, the battle for Guadalcanal proved to be extremely costly for the Japanese Empire in terms of both material losses and strategy. With Guadalcanal secure, the Solomon Islands quickly fell to American forces as Henderson Field offered a direct base of support for American air units in the area. The sheer number of Japanese troops, supplies, and naval units was also irreplaceable at this point of the war. For many historians, the American victory at Guadalcanal, therefore, was a turning point for the war effort as Guadalcanal served as a major boost to American morale, and a tremendous success for American military efforts in the Pacific.

In total, approximately 24,000 Japanese soldiers were killed during the battle, whereas the Americans suffered 1,600 killed, along with nearly 4,200 wounded. In addition, Japanese naval forces lost two battleships, four cruisers, one aircraft carrier, eleven destroyers, and six submarines. Likewise, American forces lost eight cruisers, fourteen destroyers, and two aircraft carriers.

Works Cited


This content is accurate and true to the best of the author’s knowledge and is not meant to substitute for formal and individualized advice from a qualified professional.

© 2019 Larry Slawson


Miebakagh Fiberesima from Port Harcourt, Rivers State, NIGERIA. on April 22, 2019:

The winning of war could be worst than hell at times.

Eric Dierker from Spring Valley, CA. U.S.A. on April 22, 2019:

As expected this is a fantastic written article. Wow what a war. Tenacity in the face of huge odds. I once heard that this multi battle was awarded with 20,000 new recruits on the American side. War is hell. Winning is everything.

William Francis Torpey on April 20, 2019:

Very interesting and well done, Larry. Your story is of special interest to me because my uncle, William F. Hogan, was KIA when his ship, the USS Gregory, was sunk in October 1942 after delivering a battalion of Marines to Savo Island. Thank you.

Miebakagh Fiberesima from Port Harcourt, Rivers State, NIGERIA. on April 17, 2019:

Hi, Larry, it is appreciated, please. And thanks.

Larry Slawson (author) from North Carolina on April 17, 2019:

@Liz and @Miebakagh Thank you so much! I'm glad you both enjoyed!

Miebakagh Fiberesima from Port Harcourt, Rivers State, NIGERIA. on April 16, 2019:

Hello, Larry, Iam adding this detailed historica piece tomy data bank. Thanks for sharing.

Liz Westwood from UK on April 16, 2019:

This a thorough, well-illustrated and well-structured article article. I am guessing that you will find plenty more material for future articles should you focus on the World War 2 period.

Larry Slawson (author) from North Carolina on April 15, 2019:

Thank you Cheryl! I'm so glad you enjoyed!

Cheryl E Preston from Roanoke on April 15, 2019:

Very in-depth and detail oriented. I learned much about history today.