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War Casualties


WAR CASUALTIES. The term "war casualty" applies to any person who is lost to a military unit by having died of wounds or disease, having received wounds, or having been injured but not mortally. War casualties are classified into two categories: hostile and nonhostile (disease and nonbattle injuries). A hostile casualty is any person who is killed in action or wounded by any civilian, paramilitary, terrorist, or military force that may or may not represent a nation or state. Also included in this classification are persons killed or wounded accidentally either by friendly fire or by fratricide, which occurs when troops are mistakenly thought to be an enemy force. Nonhostile casualties are not attributable to enemy action. These occur due to an injury or death from environmental elements, disease, self-inflicted wounds, or combat fatigue.

The table shows the number of persons who served in the U.S. military in each of its ten major wars, the total deaths from wounds, disease and nonbattle injuries, and wounds received but not fatal. This data shows that more soldiers, sailors, airmen, and marines died from diseases and other nonbattle injuries than from battle wounds.

It was not until the Civil War that the techniques of battlefield treatment began. The surgeon Jonathan Letterman devised a system of collecting casualties and transporting them from the battlefield to field hospitals, where doctors would perform surgery.

With the discovery of antisepsis, disease and non-battle deaths began to decline. Disease was no longer the principal threat to military forces. Prior to World War I, however, advances in technology increased weapon lethality. During the war, the number of casualties from combat wounds began to approach the number of disease and nonbattle injuries. In World War II, for the first time, battle casualties exceeded disease casualties. The medic or corpsman was first used during World War I. These individuals would accompany the infantry in combat and administer first aid to the injured, before they were evacuated

United States Casualties by Conflict
Conflict Total Who Served Battle Deaths Disease/Nonbattle Deaths Wounds Not Mortal
American Revolution
Estimated 184,000 to 250,0004,435N/A6,188
War of 1812 
Mexican-American War
Civil War (Union Only)
Spanish-American War
World War I 
World War II 
Korean War 
Vietnam War 
Gulf War 

to field hospitals. Significant advances in military medicine helped to minimize casualties in World War II. Discoveries in antibiotic drug treatments, such as penicillin and sulfa (sulfanilamide), decreased wound infections, and the use of blood plasma helped prevent shock and replace blood volume. During the Korean War, the helicopter was routinely used to evacuate casualties from the battlefield to near by mobile army surgical hospitals (MASH), where new lifesaving surgical techniques, such as arterial repair, saved many lives. These advances continued in military medicine during the Vietnam War with more sophisticated surgery and additional antibiotics and equipment. These developments contributed to just 2.5 percent of casualties dying from wounds received, the lowest number ever. During the Gulf War of 1990–1991, disease and nonbattle injury rates were markedly lower than expected. In addition, the number of combat casualties was never so high as to test the capabilities of the medical force.


Depuy, Trevor N. Attrition: Forecasting Battle Casualties and Equipment Losses in Modern War. Fairfax, Va.: Hero Books, 1990.

Reister, Frank A. Battle Casualties and Medical Statistics: U.S. Army Experience in the Korean War. Washington, D.C.: Office of the Surgeon General, Department of the Army, 1973.

U.S. Department of Defense. "Service and Casualties in Major Wars and Conflicts (as of Sept. 30, 1993)." Defense Almanac 94, no. 5 (September–October 1994).

Robert S.Driscoll

See alsoMedicine, Military .

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