Civil War ~ Military Terminology

NEW TO CIVIL WAR RESEARCH?
A beginning researcher faces several challenges when starting to look for his/her Civil War ancestor. The first of many is deciphering the unit naming conventions used. Not only do several units of the same branch have the same numerical designation because they were organized under different authority (e.g., regular army, reserves, state troops, volunteers, militia, partisan rangers, local defense troops, etc.) but some units were known by more than one numerical designation because of consolidation between units, especially after the reorganization of the Confederate States Army on April 16, 1862. If that's not bad enough, many units were known in the field by the name of the first commander and may be cited in the literature on the war only by that name. Fortunately, there are several good "secret decoder rings" on the WWW which you may find helpful.

For those just beginning who don't understand military terminology, here's a quick primer:
The COMPANY is the basic building block of regiments and battalions. They were generally recruited within a very limited geographic area, such as a town or a county and made up of about 100 privates, a captain, three lieutenants, four sergeants, four corporals, and two musicians. Not all companies raised had this full compliment of men. Companies in a regiment were designated alphabetically: A, B, C, D, E, F, G, H, I, K (the letter J was not used).

If fewer than 10 companies were raised (actually between two and ten) a BATTALION was formed. If more companies could be added to reach regimental strength (see the next paragraph) they were often redesignated. In some cases regiments were subdivided down to battalion sized units and redesignated. Battalions were normally commanded by a lieutenant colonel or major.

Once about 10 companies were raised, they were consolidated into a REGIMENT. Most of the information you will find is about the regiment. The regimental field officers and staff consisted of a colonel, lieutenant colonel, major, adjutant, and sergeant-major. A regiment at full-strength was supposed to number a little over 1,000 men; however, for various reasons it was typically half to two-thirds of that. Most regiments going into battle had 300-500 men or less. Toward the end of the war, these numbers were even smaller, especially for the Confederates.

Two or more regiments (generally three to seven or more) comprise a BRIGADE, usually commanded by a brigadier general (Confederate).

Two or more brigades formed a DIVISION. For the Confederates, a division was usually commanded by a major general.

And finally, two or more divisions comprised a CORPS usually under the command of a lieutenant general (Confederate).

NOTE: Union organization followed these same general principles, but the rank of the commanding officer of these various sized units differed slightly.