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Operation Cottage

Operation Cottage was an amphibious assault launched by Allied forces on August 15, 1943, to recapture Kiska Island in the Aleutian Islands chain from Japanese occupation during World War II. Involving approximately 34,000 U.S. and Canadian troops from the U.S. 7th Infantry Division and the Canadian 13th Infantry Brigade, the operation aimed to complete the Allied campaign in the Aleutians following the costly recapture of Attu Island earlier that year. Unbeknownst to the Allies, the Japanese garrison of about 5,400 troops had evacuated the island using a light cruiser and 10 destroyers under cover of fog on July 28–29, 1943, leaving behind booby traps but no defenders. As a result, no direct combat occurred, and Kiska was declared secure on August 24, 1943, though the operation suffered 313 casualties (including approximately 92 deaths and 221 wounded), with 28 from friendly fire, around 50 from booby traps and accidents, and 71 killed plus 47 wounded from a naval mine incident aboard the USS Abner Read on August 18. The planning for Operation Cottage began in the spring of 1943, after the intense and bloody (May 11–June 2, 1943), which had resulted in nearly 3,000 Allied casualties and highlighted the challenges of fighting in the harsh Aleutian environment of fog, rain, and rugged terrain. Allied commanders, including U.S. Admiral and Canadian General , anticipated fierce Japanese resistance on , the larger and more fortified of the two occupied islands, and thus assembled a substantial force supported by naval bombardments from June to August. Intelligence failures, including underestimation of Japanese evacuation capabilities and overreliance on aerial reconnaissance hampered by weather, led to assumptions of a heavily defended island. The operation's objective was not only to eliminate the Japanese foothold threatening but also to secure the northern Pacific flank for broader Allied advances in the war against . Execution of the landings was delayed by adverse weather, with troops finally going ashore amid thick fog and high tides on , leading to initial disorientation and instances of troops firing on each other in the mist. Over the following days, patrols swept the island's volcanic landscape, discovering abandoned fortifications, supplies, and over 150 booby-trapped sites, but no enemy forces. The lack of opposition puzzled commanders, who feared traps, prolonging until of the evacuation. Naval support included ships from U.S. 16 (North Pacific Force) and the Royal Canadian Navy, which conducted pre-invasion shelling, though much of it was ineffective due to the weather and the absence of targets. The USS Abner Read was severely damaged by a on , contributing 71 deaths and 47 wounded to the toll. Strategically, Operation Cottage marked the conclusion of the (June 1942–August 1943), restoring full U.S. control over its territory and preventing potential Japanese use of the islands as a for attacks on . However, the campaign as a whole diverted Allied resources from the central Pacific theater, and the high non-combat casualties on underscored lessons in , weather preparation, and inter-Allied coordination. Post-operation, the Aleutians served as bases for weather stations and airfields, contributing to the broader until Japan's surrender in 1945. The event remains a notable example of military operations influenced by environmental and perceptual factors.

Historical Context

Aleutian Islands Campaign

The , a remote chain stretching over 1,200 miles westward from the toward the Soviet Union's , held strategic significance during as a potential stepping stone for forces to threaten North American territories, including and the continental . planners viewed the islands as a means to establish air and naval bases that could disrupt Allied supply lines across the North Pacific and serve as a diversionary tactic during larger operations, such as the campaign, while also preventing U.S. forces from using the chain as a route to attack Japan's home islands. Although the islands' harsh weather and rugged terrain limited their practical military value, their proximity to North America raised fears of potential bombing raids on key West Coast cities like and . In early June 1942, as part of Operation AL coordinated with the Midway offensive, Japanese forces initiated their incursion into the Aleutians. Carrier-based aircraft from the First Air Fleet bombed Dutch Harbor on Unalaska Island on June 3 and 4, targeting U.S. naval facilities in a feint to draw American attention northward. Following the air raids, Japanese troops unopposedly occupied Kiska Island on June 6 and Attu Island on June 7, capturing the small local populations and establishing garrisons to consolidate control. These landings marked the only enemy occupation of U.S. soil during the war, involving approximately 8,500 Japanese personnel supported by naval assets. The responded swiftly to the Japanese occupation by bolstering its defenses in the region. The Alaskan Air Force, established on December 28, 1941, and activated on January 15, 1942, was redesignated as the on September 18, 1942, to coordinate aerial operations against the Aleutian threats, including bombing runs on Japanese-held positions. Naval forces under Task Force 16 patrolled the area, leading to key engagements such as the on March 26, 1943, where U.S. cruisers and destroyers intercepted a Japanese convoy attempting to reinforce Attu, resulting in a tactical draw but preventing the resupply. Domestically, the fueled political pressures on U.S. leaders to reclaim the islands, as public outcry over "unavenged" risked undermining and support for the , particularly amid broader Pacific setbacks. President and military commanders prioritized the Aleutian campaign to neutralize the symbolic Japanese foothold and demonstrate resolve in defending the homeland, despite the theater's secondary status compared to Central Pacific operations.

Japanese Occupation of Attu

The Island commenced on June 7, 1942, when approximately 500 soldiers from the Imperial Japanese Army's 301st Independent Infantry Battalion landed unopposed at Holtz Bay, securing the remote western Aleutian outpost as part of a diversionary operation during the campaign. The small initial force quickly overran the undefended island, capturing its sparse infrastructure and establishing a foothold amid the harsh, fog-shrouded . Over the ensuing months, reinforcements arrived via and limited surface transports, expanding the garrison to roughly 2,500 troops by early 1943 to fortify the position against anticipated Allied response. Upon arrival, the Japanese encountered and imprisoned the island's 42 Unangax̂ (Aleut) residents along with two American civilians, radio operator Charles Foster Jones and his wife Ethel "Etta" Jones, who served as the local schoolteacher. The captives were confined to their homes under guard for about three months, enduring surveillance and restricted movement while the occupiers consolidated control. In October 1942, the group was forcibly relocated by ship to internment camps near on , , where poor sanitation, malnutrition, and infectious diseases led to the deaths of approximately half the —around 25 individuals—before their repatriation in 1945; survived the ordeal, but her husband perished in captivity due to harsh conditions. To maintain their hold, the Northern Force, under Yasuyo Yamasaki who assumed command in April 1943, undertook significant engineering efforts despite the Aleutians' of relentless winds, frequent , and subzero temperatures. Troops constructed an incomplete airstrip at Alexai Point for potential air operations, along with a network of bunkers, pillboxes, and trench systems embedded in the island's steep, boggy slopes and passes, utilizing local materials and forced labor from Korean conscripts to create layered defenses aimed at repelling amphibious assaults. Sustaining the occupation proved increasingly difficult as U.S. naval forces, led by , imposed a tight around the Aleutians starting in , interdicting Japanese supply convoys and submarines through patrols and air strikes. This interdiction drastically curtailed reinforcements—limited to sporadic submarine deliveries—and essential supplies like food, ammunition, and fuel, exacerbating shortages and contributing to the garrison's effective isolation by early 1943 amid the broader pressures of the Aleutian campaign.

Planning and Preparation

Strategic Objectives

Planning for Operation Cottage, the invasion of Island, began in the spring of 1943 following the recapture of in the (May 11–June 2, 1943), which demonstrated the challenges of amphibious operations in the Aleutians but isolated the remaining Japanese garrison on . The approved the operation to complete the , driven by the need to remove the last Japanese foothold on U.S. territory and secure the northern Pacific flank against potential threats to and North American shipping routes. The primary strategic aims were to seize , the larger and more fortified of the occupied islands, to deny a base for air raids or further incursions, establish Allied airfields for bombing the , and enable focus on the central Pacific theater. Vice Admiral , as commander of North Pacific Force and Area, coordinated the effort, anticipating fierce resistance similar to Attu and assembling a large joint force to overwhelm defenses around Kiska Harbor using a . Francis W. Rockwell commanded the amphibious task force, while led the ground assault, emphasizing integrated naval gunfire and air support. This joint U.S.-Canadian operation held symbolic importance as the first major combined Allied assault, boosting morale after the costly Attu campaign. Intelligence failures plagued planning, with hampered by persistent fog leading to overestimations of strength at around 5,600 troops, including underappreciation of their evacuation capabilities via and under cover of weather. Assessments from July 1943 noted reduced enemy activity, such as no radio signals after July 28, but commanders dismissed evacuation as unlikely, resulting in preparations for a heavily defended with extensive fortifications. The rugged , including volcanic peaks over 4,000 feet, bogs, and , was anticipated based on Attu experiences, but mitigation focused on larger troop numbers rather than revised .

Allied Forces and Logistics

The Allied invasion of under Operation Cottage was commanded by Vice Admiral as the overall commander of North Pacific Force and Area, with Rear Admiral Francis W. Rockwell directing the amphibious attack force and Major General leading the Northern Landing Force comprising the bulk of ground troops. The operation involved a joint U.S.-Canadian effort totaling over 34,000 personnel, including approximately 29,000 American troops primarily from the 7th Infantry Division and about 5,300 Canadian troops from the 13th Infantry Brigade of the 6th Infantry Division. Supporting elements included the , a joint U.S.-Canadian commando unit of around 2,500 men trained for specialized raids, which was assigned to initial assault roles using rubber boats. Preparations emphasized rigorous training tailored to the Aleutian environment, with the 7th Infantry Division conducting amphibious exercises at , , in to simulate beach landings and coordinate with naval forces. The underwent extensive cold-weather and mountaineering drills at Fort Harrison, Montana, from late 1942 into early 1943, focusing on skiing, rock climbing, and survival in subzero conditions to counter the expected harsh terrain and climate. Canadian forces, arriving in July 1943, integrated through joint maneuvers on , incorporating lessons from the recent Attu campaign to refine tactics for fog-shrouded assaults and rapid inland advances. Logistical hurdles were formidable due to the Aleutians' , including gale-force winds exceeding 100 mph, perpetual fog, heavy rains, and temperatures often below freezing, which complicated equipment transport and troop acclimation. The absence of natural harbors on necessitated reliance on open-roadstead anchorages, exposing supply ships to rough seas, while the rugged, volcanic terrain limited mobility and required specialized gear such as insulated , snowshoes, and lightweight cold-weather tents to prevent exposure-related seen on Attu. Amphibious planning drew from experiences by prioritizing coordinated naval gunfire and air support, with nearly 100 warships—including battleships USS Pennsylvania, , and —providing pre-invasion bombardment, supplemented by the Eleventh Air Force's carrier-based and land-based aircraft for using LCVPs and other for the H-hour assault at 0630 on August 15. The supply chain depended heavily on forward bases in , with troops and materiel staging from —200 miles east of —as the primary assembly point, supported by for , , and reinforcements via a limited system vulnerable to weather delays. Pre-invasion included stockpiling over 330 tons of naval shells and 424 tons of bombs at Adak, but shipping constraints and the need for cold-storage provisions for perishable goods strained capacity, prompting innovations like modular supply crates for quicker unloading in adverse conditions.

Execution of the Invasion

Landings and Initial Engagements

The amphibious assault on Kiska Island, codenamed Operation Cottage, commenced on August 15, 1943, following extensive naval and aerial bombardments from early August that were largely ineffective due to persistent fog and poor visibility. The Allied invasion force, comprising approximately 34,000 troops from the U.S. 7th Infantry Division and the Canadian 13th Infantry Brigade, was supported by a naval including battleships , , and , cruisers and , and numerous destroyers. Advance elements of the 1st Special Service Force landed first in rubber boats at key points like Quisling Cove in the southern sector and near West Kiska Lake in the northern sector to secure beaches and guide follow-on waves using LCTs, LCMs, and LCVPs. Heavy fog and high winds blanketed the island, severely complicating navigation and causing landing craft to deviate from planned beaches, such as those at North Head, South Beach, and Rodman's Point. The landings were unopposed, as the Japanese garrison of about 5,400 troops had secretly evacuated on July 28–29 under cover of fog, leaving behind equipment, fortifications, and booby traps. However, the dense mist led to immediate disorientation among troops, who mistook shadows, wildlife, and even fellow Allies for enemy forces, resulting in friendly fire incidents. U.S. and Canadian units occasionally exchanged fire in the confusion, contributing to the initial casualties of 28 killed and numerous wounded from such mishaps on the first day. Environmental challenges included cold temperatures around 40°F (4°C), slippery volcanic terrain, and high tides that forced troops to wade through deep water while carrying heavy loads. By nightfall, beachheads were established, but the absence of opposition raised suspicions of traps among commanders.

Inland Combat and Japanese Defenses

In the days following the August 15 landings, Allied forces under U.S. Francis W. Rockwell and Canadian H. F. G. Letson conducted a systematic inland sweep across Kiska's rugged, fog-shrouded landscape, expecting fierce resistance from entrenched positions. Patrols from the 17th and 184th Infantry Regiments in the south, and the 87th Mountain Regiment alongside the Canadian 13th Brigade in the north, advanced through volcanic ridges, bogs, and abandoned camps toward key sites like Harbor and the main base area. No direct combat occurred, as on August 16 confirmed the island's evacuation, but troops remained cautious, probing suspected bunkers and tunnels with flamethrowers and grenades due to fears of hidden defenders. The Japanese had left behind a network of over 150 booby-trapped sites, including mined roads, rigged ammunition dumps, and explosive-equipped structures, which caused 50 casualties from traps and accidents during the operation. Elements of the 1st Special Service Force scouted Little Kiska and nearby Segula Island on August 16–17, finding no enemy but discovering stockpiles of supplies and fortifications integrated into the terrain. Persistent fog limited visibility to mere yards, isolating units and hindering coordination, while gale-force winds and rain exacerbated fatigue and exposure risks. Logistical efforts focused on unloading supplies amid the weather, with jeeps and tractors struggling on muddy paths; medical support treated cases of trench foot and exhaustion alongside combat-related injuries. On August 18, the destroyer USS Abner Read struck a Japanese naval mine off the island's coast, resulting in 71 deaths and 47 wounded, further highlighting the operation's hazards despite the lack of opposition. The search continued until August 24, when Kiska was declared secure.

Climax and Resolution

Search Operations and Incidents

Following the unopposed landings on , 1943, Allied troops from the U.S. 7th Infantry Division and Canadian 13th Infantry Brigade began extensive patrols across 's rugged, fog-enshrouded terrain to locate and eliminate defenders. Expecting fierce resistance similar to Attu, commanders ordered systematic sweeps of the island's volcanic landscape, including the heavily fortified areas around Kiska Harbor and the North Head ridge. Over the next several days, patrols encountered abandoned camps, dumps, and over 150 booby-trapped positions rigged with grenades, mines, and tripwires, which caused approximately 50 casualties from accidents and traps. The search was complicated by persistent thick fog, high winds, and disorientation, leading to additional incidents that killed 28 troops as units mistakenly engaged each other in the . No forces were found, prompting suspicions of hidden tunnels or traps, which prolonged operations and heightened tension among the 34,000 invaders. Engineers and cleared potential hideouts using demolitions and flamethrowers, but the absence of opposition gradually confirmed failures regarding the evacuation on July 28–29, 1943. A significant naval incident occurred on August 18, 1943, when the destroyer USS Abner Read (DD-526), on anti-submarine patrol near Kiska, struck a drifting Japanese mine at approximately 01:50, severing 67 feet of its stern. The explosion killed 71 sailors (including 70 missing presumed dead) and wounded 47 others, marking the operation's most severe single loss despite the lack of enemy presence. Rescue efforts by accompanying ships saved the remaining crew, and the damaged vessel was towed to Adak for temporary repairs before heading to the continental U.S.

Confirmation and Withdrawal

By August 20, 1943, accumulating evidence—such as fresh evacuation traces, empty fortifications, and captured documents—convinced Allied commanders that held no organized resistance. However, isolated patrols continued until August 24 to ensure no holdouts remained, at which point W. Rockwell declared the island secure. The operation concluded without direct combat, but the nine-day occupation revealed the garrison's successful under cover of weather, leaving behind extensive defenses but no personnel. In total, Operation Cottage resulted in approximately 313 Allied casualties, primarily non-combat: 28 from , around 50 from booby traps and accidents, and 71 deaths plus 47 wounded from the Abner Read incident. No Japanese casualties occurred on , as the 5,400 troops had evacuated intact. The resolution underscored the challenges of Aleutian operations, with troops withdrawing by late August to bases on nearby Adak and , allowing the Aleutians campaign to end.

Aftermath and Legacy

Casualties and Losses

Operation Cottage resulted in no direct combat with Japanese forces, as the island was found abandoned upon landing. Allied totaled 313, all non-combat: 92 killed and 221 wounded among the approximately 34,000 U.S. and Canadian troops. These included 28 deaths from incidents in the fog, about 50 from booby traps and accidents, and around 130 from and disease due to the harsh weather and terrain. Additionally, the USS Abner Read struck a off on August 18, 1943, killing 71 sailors and wounding 47, contributing significantly to the toll. The garrison of approximately 5,400 had evacuated under cover of fog on July 28–29, 1943, suffering no combat losses during the operation. They left behind over 150 booby-trapped sites, abandoned fortifications, and supplies, which were systematically destroyed or captured by Allied patrols. No Japanese prisoners were taken on Kiska. Kiska had no civilian population at the time, as the Unangan people had been evacuated by U.S. forces in 1942 to avoid Japanese occupation, with some communities facing hardships in relocation camps similar to those in the broader Aleutian campaign. Material losses were minimal for the Allies beyond the Abner Read damage and minor weather-related naval incidents, though the operation highlighted logistical strains from fog and high tides.
SideKilledWoundedNon-Combat/OtherPrisoners/CapturedTotal Affected
Allies (U.S./)92221~130 (trench foot, disease); 28 (); ~50 (booby traps/accidents)N/A313 out of ~34,000
Japan00N/A05,400 evacuated

Strategic and Operational Lessons

Operation Cottage concluded the on August 24, 1943, when was declared secure, restoring full U.S. control over the territory and eliminating the last Japanese foothold in the chain. This secured the northern Pacific flank against potential threats to and , though the overall campaign diverted significant resources—over 100 ships and 34,000 troops—from central Pacific operations with limited strategic gains beyond territorial recovery. The operation revealed critical intelligence failures, including overreliance on weather-hampered reconnaissance and underestimation of Japanese evacuation capabilities, leading to assumptions of heavy defenses despite the island's emptiness. Environmentally, the Aleutians' fog, rain, and rugged terrain caused disorientation, , and non-combat injuries, prompting improvements in U.S. for amphibious assaults—such as better weather forecasting, fog-penetrating signals, and cold-weather gear—that influenced later operations like . Inter-Allied coordination between U.S. and Canadian forces was tested, highlighting needs for unified command in joint operations. The campaign's legacy includes its role as a "forgotten" theater, with post-war use of Aleutian bases for weather stations and airfields supporting Pacific logistics until 1945. As of 2025, remnants like and booby traps continue to pose hazards, restricting access and requiring occasional clearance efforts within the Alaska Maritime National Wildlife Refuge. The event exemplifies perceptual bias in military planning and the human cost of environmental factors in warfare.