This is a list of American Civil War units, consisting of those established as federally organized units as well as units raised by individual states and territories. Many states had soldiers and units fighting for both the United States (Union Army) and the Confederate States (Confederate States Army). The border states had both Confederate and Union units, and in many of the Confederate states Union forces organized Union units from individuals who swore loyalty to the United States.
United States
Federal organized
- United States Colored Troops
- United States Regular Army
- United States Volunteers
- District of Columbia
State forces
- Alabama
- Arkansas
- California
- Connecticut
- Delaware
- Florida
- Georgia
- Illinois
- Indiana
- Iowa
- Kansas
- Kentucky
- Louisiana
- Maine
- Maryland
- Massachusetts
- Michigan
- Minnesota
- Mississippi
- Missouri
- Nevada
- New Hampshire
- New Jersey
- New York
- North Carolina
- Ohio
- Oregon
- Pennsylvania
- Rhode Island
- South Carolina
- Tennessee
- Texas
- Vermont
- Virginia
- West Virginia
- Wisconsin
Territories
- Colorado Territory
- Dakota Territory
- Indian Territory (Confederacy)
- Nebraska Territory
- New Mexico Territory
- Washington Territory
- Utah Territory
Confederate States
Confederate organized
State forces
- Alabama
- Arkansas
- California
- Florida
- Georgia
- Kentucky
- Louisiana
- Maryland
- Mississippi
- Missouri
- North Carolina
- South Carolina
- Tennessee
- Texas
- Virginia
- West Virginia
Territories
- Arizona Territory
- Indian Territory (also known as Oklahoma)