620,000
The number of soldiers who died between 1861 and 1865, generally estimated at 620,000, is approximately equal to the total of American fatalities in the Revolutionary War, the War of 1812, the Mexican War, the Spanish American War, World War I, World War II, and the Korean War, combined.
https://www.nps.gov › travel › death
Death and Dying–Civil War Era National Cemeteries