Photograph of Nimitz and senior officers paying their respects at a Marine cemetary

National Archives #80-G-213113

Casualties are the brutal reality of warfare. The number of deaths resulting from the Second World War remains uncertain, but was around 70 million persons. Of these, around 22 million were military deaths while the remainder were civilians killed during military operations, through famine, or in crimes against humanity. This represents about 3% of the total world population at the time. Casualties in the Pacific War numbered around 36 million or 50% of the total casualties of the Second World War.

Total casualties in Asia and the Pacific by nation and type

Killed or missing
Prisoners of war
Civilian deaths
9,470 13,997 21,726

6,860 24,200
68,890 2,000,000
1,740,000 94,00041,4402
Netherlands East Indies     


United Kingdom1 5,670 12,840 50,016
United States
111,606   253,14221,580

Blank entries indicate that estimates are unavailable, but the numbers likely are small.
1Includes only losses in ground combat.
2Prior to 15 August 1945.

In the broadest sense, military casualties include all losses of military personnel, whether from death or wounds in combat, surrender, illness, accidents, or desertion. About 4% of U.S. troops were unavailable for combat at any given moment during the war. In the Pacific, with its poor living conditions, the great majority of these were not combat-related. Over the course of the Second World War, the U.S. Army recorded about 17 million hospital admissions globally for illness or accident, versus about a million combat casualties. Indeed, in the early days of the war, the Allied armies experienced about 100 casualties from heat or disease for every combat casualty.

A similar picture is given by the casualty statistics of 20 Indian Division. During one six-month period, there were 2345 battle casualties, 1118 malaria and typhus cases, 697 cases of dysentery, 205 cases of venereal disease, 210 cases of skin disease, 170 psychiatric casualties, 100 accidents, 321 minor injuries, and 2784 other hospital admissions (Hastings 2007.) This was not unusual. During the first six months of 1944, 14 Army experienced 40,000 combat casualties and 282,000 casualties from illness.

About 24.2% of Japanese soldiers and 19.7% of Japanese sailors died during the Second World War, contrasted with 3.66% of U.S. Marines, 2.5% of U.S.soldiers, and 1.5% of U.S. sailors. Casualties in China were immense even before war broke out in the Pacific: The Japanese had suffered over 180,000 dead (including 48,344 dead from illness) and over 323,700 wounded (including 36,470 permanently disabled) by October 1941.

Civilian casualties are difficult to quantify. Civilian deaths resulting directly from military action or massacre are clearly attributable to the war, but deaths from disease, famine, or other hardship are more ambiguous, since these also occur in peacetime.  The best one can do is to estimate excess deaths, which is the number of deaths during the war beyond what would have been expected under peacetime conditions. Such estimates are inherently uncertain. The civilian Indian deaths in the table above are primarily from the Bengal famine of 1943, for which estimates of excess deaths range from 1.5 to 3 million. The civilian Chinese deaths are the best estimate from recent archival research (cited by Hsiung and Levine 1992) but may be an overestimate (Mitter [2013] estimates 14 to 20 million total Chinese dead), while the estimate of Japanese civilian casualties, coming primarily from the strategic bombing campaign, is likely an underestimate. The figure for the Netherlands East Indies, arising from famine and forced labor, is also highly uncertain.

Combat Casualties. In the Western military tradition, armed forces attempted to impose their will on the enemy through the use of their firepower to inflict casualties. A unit was usually rendered hors de combat long before its casualty rate approached 100%. This was true even of the Japanese, whose resignation to death in battle astonished Westerners.

In the Allied armies, approximately three men were wounded in action for every man who was killed on the battlefield or died of his wounds. This relatively high survival rate was made possible by advances in medicine that meant that a wounded man who survived long enough to reach a field hospital had an excellent chance of recovery. The corresponding figure for the Japanese Army is nothing short of appalling: The state of Japanese military medicine and the nature of Japanese tactics (such as staging massed frontal assaults or fighting to the death in hopeless defensive positions) translated into a 95% death rate among combat casualties.

Statistics for 6 Army on Leyte indicate that almost half of all fatal wounds were from small arms fire, and a little more than half of fatal small arms wounds were from hits to the torso, with head wounds accounting for about 20% of fatalities. On the other hand, the majority of nonfatal wounds were inflicted by shell or grenade fragments.

Some idea of U.S. casualty rates can be gleaned from the following table of total wartime casualties for some of the divisions that served in the Pacific (Frank 1999).

         Casualties in selected U.S. divisions

Total Battle
Killed or
Died of Wounds



New Guinea, Luzon, southern Philippines
New Guinea, Luzon
Bismarcks, southern Philippines, Luzon
New Guinea, Luzon, southern Philippines
Guadalcanal, northern Solomons, New Guinea, Luzon
Eniwetok, Guam, Leyte, Okinawa
Palau, Leyte
1 Cavalry
New Guinea, Bismarcks, Leyte, Luzon
11 Airborne
New Guinea, Leyte, Luzon
2 Marine
Guadalcanal, Tarawa, Saipan, Tinian, Okinawa
3 Marine
Bougainville, Guam, Iwo Jima
5 Marine
Iwo Jima

The total dead or missing were 41,592 for all U.S. Army ground troops in the Pacific and southeast Asia, with another 145,706 wounded. The Marine Corps and attached Navy corpsmen suffered total casualties of 23,160 killed or missing and 67,199 wounded.

Average casualty rates for U.S. units in combat are tabulated below, in rates per thousand men committed per day (ibid.)

          Average casualty rates for U.S. ground combat units

Pacific Amphibious
Euopean Protracted
Killed in action
Wounded in action
Missing in action

It is notable that the fraction of fatal casualties in the more intense combat (24%) is significantly greater than in the more protracted combat (17%). This likely reflects the higher reliance on artillery rather than small arms to wear down the enemy in extended campaigns.

Western air and naval forces tended to suffer a much higher percentage of deaths among their combat casualties than did Western ground forces. The U.S. Navy lost 31,157 killed in action out of a total of 62,858 combat casualties in the Pacific, a figure of nearly 50%. The U.S. Army Air Forces lost 15,694 dead and missing out of a total of 24,230 casualties in the Pacific, a figure of 65%.

Total U.S. combat casualties in the war against Japan were thus 111,606 dead or missing and another 253,142 wounded.

Japanese military casualties from 1937-1945 have been estimated at 1,834,000, of which 1,740,000 were killed or missing. Some 388,600 of these were incurred in China, another 210,830 in southeast Asia, and the rest in the Pacific. Of these, some 300,386 were naval fatalities, and some 334 Japanese warships were sunk during the war.

Chinese military casualties are uncertain, but a reasonable estimate is about four million dead and three million wounded.

In the Pacific, the British lost 5,670 dead or missing and 12,840 wounded, the Australians 9,470 dead or missing and 13,997 wounded, and India 6,860 dead and 24,200 wounded. The figures for Britain and India are from Ellis (1985) and are for ground forces only, to which should be added at least 1100 sailors lost with Force Z and in other naval actions in the Far East. Ellis' figure may be a serious underestimate, and total combined British and Indian combat dead in the Far East may have been as high as 28,000  (Street 2012, private communication).

Civilian casualties were very heavy in certain theaters of the Pacific War. Japan suffered at least 393,400 civilian deaths and another 275,000 civilians wounded. The best recent estimate of Chinese civilian deaths, calculated from archival records, stands at 18 million. These dwarf the civilian casualties of the other Allies, though these were sometimes locally heavy, as at Manila. The war in China also produced an estimated 95 million refugees.

Combat Fatigue. A significant percentage of casualties in combat were psychological casualties, as much as 30% for poorly led and poorly trained troops, such as 43 Division at New Georgia. A more typical figure was 5% to 10%. Japanese troops were not immune to combat fatigue, but because of differences in culture and military tradition, it manifested itself differently. Japanese troops who broke down psychologically were very likely to commit suicide, either directly (such as with their own grenades) or indirectly (such as by banzai charges into massed Allied fire.)

Surrender. Large numbers of Allied troops were forced to surrender during the first months of the war, when they were caught up in Japan's carefully prepared opening offensive. Almost a third of all Allied prisoners of war died in Japanese camps by the time the war ended, a reflection of the brutal treatment they received from their captors. Commonwealth forces actually suffered more deaths in Japanese POW camps than in combat. The British lost 50,016 prisoners of war in southeast Asia, the Australian 21,726, and the Indians 68,890. The American forces lost 21,580 prisoners of war, most of them in the Philippines.

Once the Allied counteroffensive got under way, surrender by Allied troops became a rare phenomenon.

Few Japanese troops surrendered before August 1945. As the Allied counteroffensive rolled forward, and Japanese garrisons were trapped on small islands from which there was no escape, Japanese garrisons literally fought to the death. Typically just 1 to 3 percent of a trapped garrison would surrender, while the remainder died in combat or committed suicide. The impression that the Japanese were more willing to surrender as the war became hopeless was largely an illusion. The Allies were taking more prisoners, but they were also fighting larger enemy forces, and the 1 to 3 percent figure held up to the end of hostilities.

Of those Japanese taken prisoner, it is estimated that only one-third were actively looking for the opportunity to surrender. The remainder were capture while too sick or badly wounded to resist or because they stumbled into Allied positions and were taken by surprise.

Surrender may have been considerably more common among reservists in China. Historian Kawano Hitoshi (in Peattie et al. 2011) reports that 37 Division, a Class C "security" division in China, had approximately 7000 men taken prisoner over the course of the war. I have found no statistics from the Chinese side on the numbers of prisoners of war taken or their fate. 

Illness. Illness accounted for the overwhelming majority of Allied casualties during the Pacific War. Malaria was the main culprit, but dengue, scrub typhus, and other tropical diseases, together with FUO ("Fever of Undetermined Origin", which sometimes was a symptom of combat fatigue), took their toll as well. American hospitalizations for illness worldwide numbered around 15 million.

Stavation. Deaths from starvation were not unknown among the Americans during the Bataan campaign, but the great majority of armed soldiers who died of starvation were Japanese or Chinese. The Allied strategy of leapfrogging strong Japanese garrisons left these isolated from resupply, and since surrender was unthinkable to their commanders, these garrisons were forced into a Stone Age existence of trying to grow sufficient food for survival in the jungle. It is likely that most of Adachi's 18 Army, cut off in New Guinea, died of starvation. Hyakutake's 17 Army in Bougainville suffered a similar fate. Overall, an appalling 60% of Japan's military dead were lost to starvation.

Chinese logistics were grossly inadequate throughout the war, and some observers reported corruption in the form of commanding officers stealing the money allocated to their formations for rations. However, Chinese military deaths due to starvation are impossible to quantify due to lack of any but anecdotal information.

The majority of those who starved during the Pacific War were civilians. These included somewhere between 1.5 million and 3 million Indians in the Bengal famine of 1943, which was a consequence of the loss of rice imports from Japanese-occupied Burma, the worldwide shortage of shipping, and incompetence on the part of the British-led administration. Millions more died in China (including at least two million in Honan province alone) and in southeast Asia from shortages brought about by the rapacious demands of the Japanese occupation.

Accidents. In the U.S. Army worldwide, accidents accounted for about 2 million hospitalizations. Air operations were especially hazardous. Some 13,000 American airmen were killed accidentally, while the Royal Air Force lost 787 officers and 4540 other ranks to accidents.

Absence Without Leave and Desertion. Absence without leave was failure to report for duty. This became desertion if the soldier or sailor intended to permanently separate himself from the armed forces. Though desertion in time of war was universally regarded as a capital offense, no American serviceman in the Pacific Theater (and only one in Europe) suffered the ultimate penalty for desertion.

In the U.S. Army, a division shipping for an amphibious assault typically found about 1% of its personnel absent without leave. In the Marine Corps, the figure was sometimes as low as 0.1%, a reflection of the superior esprit de corps of the all-volunteer force. Leckie (1962) claims that the number of men absent without leave from 1 Marine Division when it shipped out for Guadalcanal was less than a dozen.

A secret Japanese Army report in 1942 claimed that desertions to the enemy in China peaked at just 35 men in 1939 (CINCPAC 1945). However, the same report made it clear that being captured while unconscious from wounds was considered desertion! The reality was that desertion was far more common than Japanese military leaders were willing to admit. Kawano (in Peattie et al. 2011) reports that 37 Division, a Type C "security division" in China, suffered about 750 desertions over the course of the war, of whom perhaps 100 joined the Chinese Communist 8 Route Army. Collie and Marutani (2009) interviewed a Japanese veteran of the Kokoda campaign who was pressed into service as a light machine gunner to replace a soldier who "had gone to the rear without permission." U.S. forces on Okinawa discovered large numbers of young men with concealed weapons among the native Okinawans, but it was not clear how many were Okinawan conscripts who had truly deserted or Japanese guerrillas. Desertion became a serious concern of Japanese commanders in Burma from 1944 on.

I have found one documented case of Japanese soldiers deserting to the Americans. A handful of enlisted men from a communications unit on Okinawa, who were privy to more information on the course of the war than the average Japanese soldier, concluded that "they might be better off if Japan were defeated; Japan might then become one of the states of the United States or a republic like France" (Straus 2003). The men slipped away from their unit, took a small boat to the nearby island of Kume Jima, were picked up by a Japanese naval unit from which they deserted a second time, and surrendered to the first Americans they could find.

Desertions from the Chinese Army are almost impossible to quantify but were likely a huge drain on manpower. Initially, desertion was quite low; but by the time of Pearl Harbor, the percentage of conscripts had increased greatly and desertions became very common. According to Larrabee (1987), following the collapse of the Allied defense in Burma, Chinese deserters took to banditry and terrorized refugees attempting to escape to India. Stilwell's headquarters claimed that Chinese pack animals were often in very poor shape because "The Chinese are very reluctant to graze their animals for fear of losing both the animals and the soldiers through desertion" (Romanus and Sunderland 1952), and there was a real danger of mass desertion during the peak of the Japanese Ichi-go offensive.


Allen (1984)

"Army Battle Casualties and Nonbattle Deaths in World War II" (1953-6-1; accessed 2011-10-30)

Bergerud (1996)

CINCPAC (1945; accessed 2011-6-17)

Collie and Marutani (2009)

Collingham (2011)

Dunnigan and Nofi (1998)
Ellis (1995)

Evans and Peattie (1997)

Frank (1999)

Gruhl (2010)
Hastings (2007, 2011)

History of U.S. Marine Corps Operations in World War II (5 volumes; accessed 2011-10-30)

Hsiung and Levine (1992)

Larrabee (1987)

Leckie (1962)

Lewin (1976)

Mitter (2013)

Peattie et al. (2011)

Romanus and Sunderland (1952; accessed 2012-2-4)

Sledge (1981)

Straus (2003)

Tanaka (1998)

"U.S. Navy Personnel in World War II: Service and Casualty Statistics" (accessed 2011-10-30)

Valid HTML 4.01 Transitional
Web Site Counters