Casualty Figures of Major American Wars Since 1775

We’re told that freedom isn’t free, and for America, its cost has come not just in dollars but in the lives of our servicemen and women.

To compile a list of the deadliest wars fought by the U.S. between 1775 and 2022, 24/7 Tempo reviewed a report by the data site Statista, which drew statistics from the American Battlefield Trust, an organization that preserves America’s battlegrounds, and the U.S. Department of Defense.

Since the nation’s birth, the United States has often been at war or in some form of armed conflict. We have fought in 11 wars over the past 250 years, some declared and some undeclared. (These are the deadliest battles in U.S. history.)

In the 18th and 19th century, disease posed the greatest threat to soldiers outside the battlefield. Poor sanitation led to the spread of dysentery, smallpox, and other communicable diseases. Many more soldiers succumbed to disease than enemy-inflicted wounds. (These are the 12 wars where the most Americans died outside of combat.)

That was the case in World War I when more than half of the nearly 117,000 American fatalities occurred because of disease and other causes. About 45,000 American servicemen perished from influenza and pneumonia during the pandemic of 1918, which would kill some 50 million people worldwide.

Only in 20th- and 21st-century wars have battlefield fatalities exceeded non-battlefield deaths. At the same time, many of those wounded in combat who would have died from their injuries in earlier times now have a better chance of surviving because of preventive care, battlefield medicine, evacuation practices, and personal protective equipment.