Antietam National Battlefield - Casualties of Battle (U.S. National Park Service)

Casualty Does Not Equal Dead
Casualties include three categories: 1) dead; 2) wounded; and 3) missing or captured. In general terms, casualties of Civil War battles included 20% dead and 80% wounded. Of the soldiers who were wounded, about one out of seven died from his wounds. Over 2/3 of the 622,000 men who gave their lives in the Civil War died from disease, not from battle.

Antietam Casualties

Approximate Numbers	Union	Confederate	Total
Killed	2,100	1,550	3,650
Wounded	9,550	7,750	17,300
Missing/Captured	750	1,020	1,770
Total	12,400	10,320	22,720

Note: Because of the catastrophic nature of the Battle of Antietam, exact numbers of casualties were virtually impossible to compile. The sources for these figures are The Official Records of the War of the Rebellion and the Antietam Battlefield Board.

Approximate Casualties by Phase of Battle		Union	Confederate	Total
Morning Phase	Engaged	23,600	20,100	43,700
	Casualties	7,280	6,580	13,860
Mid-Day Phase	Engaged	10,000	6,800	16,800
	Casualties	2,900	2,600	5,500
Afternoon Phase	Engaged	13,800	7,150	20,950
	Casualties	2,600	1,120	3,720

Source: The Antietam Battlefield Board

Worst Civil War Battles
Antietam was the bloodiest one-day battle of the Civil War. But there were other battles, lasting more than one day, in which more men fell. The numbers below are total casualties for both sides.