The United States Army in the American Civil War was mostly made up of regiments of infantry and cavalry and batteries of artillery. With the exception of a small number of units from the United States Regular Army, most were organized, armed and equipped by the individual states and taken into national service.

Of the nineteen free states, all but Kansas, California and Oregon sent one or more regiments to the Eastern Theater, although the majority of the men from Ohio to the west fought elsewhere.

Of the slave states that remained in the Union, Missouri and Kentucky sent no troops to the east. Maryland sent units to both sides. Delaware sent several thousand men to the Union army and was the only slave state that provided no organized units to the Confederacy. West Virginia was part of Virginia until the war. But much of it was strongly pro-Union and broke away to become an independent state in 1863.

Select any state from the map or the menu to see information on its regiments and batteries.

Map of the Northern states during the Civil War

Contributions of men and units by each state to the Union army*:

Connecticut 53,721 men 33 regiments and 3 batteries
Delaware 12,280 men 10 regiments and 2 batteries
District of Columbia 15,181 men 3 regiments
Illinois 256,868 men 173 regiments and 35 batteries
Indiana 195,285 men 167 regiments and 26 batteries
Iowa 75,797 men 64 regiments
Maine 65,077 men 36 regiments and 7 batteries
Maryland 42,713 men 24 regiments and 6 batteries
Massachusetts125,747 men 80 regiments and 48 batteries
Michigan 86,866 men 79 regiments and 14 batteries
Minnesota 24,017 men 14 regiments and 3 batteries
New Hampshire 33,055 men 21 regiments and 1 battery
New Jersey 68,685 men 44 regiments and 5 batteries
New York 413,686 men 316 regiments and 77 batteries
Ohio 309,906 men 249 regiments and 42 batteries
Pennsylvania 323,629 men 291 regiments and 35 batteries
Rhode Island 21,358 men 18 regiments and 10 batteries
Vermont 32,669 men 20 regiments and 3 batteries
West Virginia 32,068 men 27 regiments and 8 batteries
Wisconsin 91,194 men 59 regiments and 13 batteries
United States Regular Army 16 regiments and 60 batteries
United States Colored Troops 175 regiments
United States Veteran Infantry 9 regiments

  *Only states that contributed to the Eastern Theater are shown in the table, but contributions of men and units shown in the table are for all theaters.